Sweet Potato Gratin
Sweet Potato Gratin
Ingredients
Equipment
Method
- Preheat your oven to 375.
- Butter a 8 x 5 casserole dish.
- In a small dish, mix the kosher salt and spice rub together.
- Layer the bottom of the casserole dish with slices of sweet potato, slightly overlapping each slice.
- Sprinkle the top with approximately one-third of the spice rub and pecorino Romano.
- Repeat with two more layers. Top with the heavy cream.
- Cover with aluminum foil. Bake on the middle rack for 30 minutes. Take the aluminum foil off and cook for another 20-30 until the cream is bubbly and the cheese is slightly browned.
- The potatoes should be fork tender. Serve and enjoy!
- Put all ingredients into a mason jar and shake. This rub is great on chicken and pork. This can be stored in your spice cabinet up to a year.
Video
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Let us know how it was!Make-ahead & storage for Dr. J’s All-Purpose Rub
Combine the listed rub ingredients and store the blended spice mix in the spice cabinet for up to a year. The rub is suitable for use on chicken and pork.
Tips for slicing and assembling your sweet potato gratin
Because the gratin is made with peeled, thinly sliced sweet potatoes, keeping slices consistent helps the layers finish at the same time. Thin, uniform slices let the cream penetrate the potatoes more evenly so nearby pieces reach the same tenderness.
Overlapping slices slightly helps the dish hold together and lets the cream and cheese coat each piece as the gratin bakes, producing a cohesive, attractive layer structure.
Why the covered-then-uncovered bake sequence is used
Covering the dish during the initial bake traps steam and gently softens the sweet potatoes so the interior becomes tender without the top developing too much color. Uncovering for the final portion of baking allows surface moisture to evaporate and the cheese on top to brown, producing a pleasing color and texture while the interior finishes cooking.
What pecorino Romano brings to this gratin
Pecorino Romano is an aged sheep’s-milk cheese with a firm texture and a sharp, salty, tangy flavor. In the gratin it adds savory, umami notes and saltiness that balance the natural sweetness of the potatoes and enrich the cream. Because the cheese is grated, it melts and distributes through the layers as the dish bakes.
How to tell when your sweet potato gratin is done
Look for a combination of cues: a fork should pass through a slice in the center with little resistance (often called “fork tender”); the cream should be bubbling around the edges; and the top should show some light browning where the cheese has melted. If the top is browned but a center slice still resists the fork, the interior hasn’t fully softened—the covered-then-uncovered approach helps prevent over-browning while the center finishes cooking.
Watch Dr. J Make Sweet Potato Gratin
Watch Dr. J make Sweet Potato Gratin and see how it comes together.
