Purple Sweet Potato Gratin with Datil Jerk


I spent last weekend in Orlando representing First Coast Fresh as part of the Fresh From Florida booth, sponsored by the Florida Department of Agriculture and Consumer Services.  A special shout out to David Dinkins (UF/IFAS Sustainable Agriculture and Food Systems Specialist), for inviting us to participate!  It was absolutely amazing to see the vast array of produce from all over the world, and to be part of a team focusing on new and alternative crops from Florida’s First Coast.  Charles Ray and I were educating the public on the datil pepper and showcasing our award winning datil pepper products from OSA Gourmet.  It’s amazing how few people know about the datil pepper.  If you want to learn more, check out my blog post on The History of the Datil Pepper.

Danny Johns and his sister Dorrie brought their Purple Palmetto sweet potatoes, grown on Blue Sky Farms in Hastings, Florida which is just down the road from St. Augustine.  I absolutely love sweet potatoes, but had never eaten a purple one.  They look like your typical orange sweet potato in shape and size, but have a deep purple skin and are a gorgeous, jewel-like, amethyst color on the inside.  The texture is different as well, as they are denser and drier, requiring longer cooking times than typical sweet potatoes.  And they have a more subtle flavor, a less “sweet” sweet potato.  You can eat sweet potatoes raw, and these would be amazing grated into a coleslaw or on top of a green salad.

Fun Facts:
  Sweet potatoes and yams are not the same thing.  Botanically, they are two different and distinct species of vegetables.

Here’s a cool quiz about the differences and similarities between sweet potatoes and yams, taken from the North Carolina Sweet Potato Commission’s website.  (

Sweet Potato, Yam or Both?

  1. I am a tuberous root with sweet moist flesh.
  2. I am originally from Africa and seldom sold in U.S. markets.
  3. I am super sweet and can grow over seven feet in length!
  4. My skin can range from thin and pale to dark and thick.
  5. I am toxic when eaten raw, but perfectly safe when cooked.
  6. I have rough skin that is difficult to peel and can even be hairy at times, but it softens when baked.
  7. My flesh can sometimes be purple!
  8. I have an oblong body with tapered ends.


  1. Both. Sweet potatoes and yams are considered tuberous roots, and both are sweet and delicious.
  2. Yam. Are you surprised? Yams grow in tropical climates, primarily in South America, Africa and the Caribbean.
  3. Yam. They have a higher sugar content than sweet potatoes and can grow to be enormous!
  4. Sweet potato. Paler skinned sweet potatoes have white flesh which is not as sweet and moist as the darker-skinned, orange-fleshed sweet potatoes.
  5. Yam. Unlike the sweet potato, yams must be cooked to be safely eaten. Preparation is a time-consuming process involving several minutes of pounding and boiling to remove toxins.
  6. Yam. Sweet potato skin is thinner and smoother.
  7. Both. Purple Okinawan sweet potato is often confused with the purple yam called ube.
  8. Sweet potato. It can be short and fat or long and thin, but it will always taper at the ends.

Nutrition Facts:  Anthocyanins, the same pigment found in berries like strawberries, blueberries and acai, grapes, red onions, kidney beans and tomatoes, is responsible for the deep purple color.  Anthocyanin is a flavonoid with antioxidant properties.  Antioxidants help knock out free radicals, which are chemical by-products in the human body known to damage cells and contribute to the development of certain diseases.  Anthocyanins from natural food sources, like purple sweet potatoes, have anti-inflammatory, anti-cancer and anti-viral benefits. Plus, purple sweet potatoes are loaded with fiber, which helps keep your digestive tract flowing smoothly and may lower your cholesterol levels.

With approximately 4 milligrams of protein per cup, calcium, potassium, vitamin B6, vitamin C, and iron, this low-fat, low-cholesterol vegetable is a powerhouse of nutritional benefits.

Now that you know how nutritious these babies are, it’s time to get in the kitchen and get on with the fun part – cooking and eating.  Those purple beauties became a gorgeous, savory, sweet potato gratin.  Asiago cheese and OSA Gourmet Datil Jerk Seasoning, are the perfect compliments to thinly sliced purple sweet potatoes.  I decided to lighten up my usual gratin recipe by using low-fat (2%) evaporated milk instead of cream.  For example, a tablespoon of heavy cream has 52 calories with 50 calories from fat.  A tablespoon of low-fat evaporated milk has 25 calories, and only 5 calories from fat.  Huge difference!  It was just as creamy, and who needs all those extra calories?  If you really want to use heavy cream, go ahead on.

Most gratins have some kind of crumb topping.  I decided to go without, but you could certainly add buttered panko breadcrumbs if you wish.

Using a food processor or mandoline makes slicing the potatoes a breeze and ensures that your slices are the same thickness, so they cook more evenly.

Purple Sweet Potato Gratin with Datil Jerk

Prep Time 10 mins
Cook Time 1 hr
Total Time 1 hr 10 mins
Course Vegetarian
Cuisine Vegetarian
Servings 6
Calories 378 kcal


  • 2 pounds purple sweet potatoes, thinly sliced (1/8 inch)
  • 1 12oz can low-fat (2%) evaporated milk
  • 2 teaspoons Old St Augustine Datil Jerk Jamaican Seasoning
  • 1 Tablespoon unsalted butter
  • 1 large sweet onion, sliced thinly
  • 1 clove garlic, minced
  • 2 cups Asiago or Gruyere cheese, grated


  • Preheat oven to 375 degrees Fahrenheit.
  • Prepare a baking dish by spraying with cooking spray to prevent the potatoes from sticking, and set aside.
  • Wash, peel, and then thinly slice purple sweet potatoes using a mandoline or food processor.
  • Soak potato slices in a large bowl of cold water while preparing the rest of the ingredients.  This prevents the potatoes from oxidizing.
  • Pour the evaporated milk into a small sauce pan and add the 2 teaspoons of Old St Augustine Datil Jerk Jamaican Seasoning Blend. Stir to incorporate the seasoning into the milk.
  • Heat the evaporated milk over medium-low heat, stirring frequently, until just gently simmering.  Do not boil or the milk will curdle.  Remove from heat.
  • In a skillet, saute the onions in the tablespoon of butter until translucent but not browned.
  • Add the garlic to the skillet and cook another 3-4 minutes to release the flavor of the garlic.  Remove from the heat.
  • Drain the potato slices.
  • Stir the milk and pour a small amount into the prepared baking dish.
  • Top with one third of the potatoes.
  • Layer half of the onions on top of the potatoes and sprinkle with one third of the cheese.
  • Add another layer of potatoes and the rest of the onions and sprinkle with cheese.
  • Top with the remaining potato slices.
  • Pour the warm milk over the potatoes
  • Top with the remaining cheese.
  • Cover casserole dish loosely with foil.
  • Bake at 375 degrees for 45 minutes.  Remove foil and continue to bake for another 15 minutes, or until the cheese is golden and bubbly.  You can insert a toothpick into the potatoes to test for doneness.  The potatoes should be soft, but not mushy.

Stay Spicy!


Prep Time: 10 minutes

Cook Time: 1 hour

Serves: 6

Calories: 378

Products Used

datil jerk jamaican seasoning 3 point 5 oz