2 1-pound red-skinned sweet potatoes (yams), rinsed, patted dry, pierced all over with fork
1 12-ounce container fresh ricotta cheese, drained in sieve at least 2 hours
1 cup finely grated Parmesan cheese (about 3 ounces)
2 tablespoons (packed) golden brown sugar
2 teaspoons plus 2 tablespoons sea salt
1/2 teaspoon freshly ground nutmeg
2 ¾ cups (about) all purpose flour
1 cup (2 sticks) unsalted butter
1 tablespoon brown sugar
¼ teaspoon cinnamon
1/3 cup chopped pecans
How to make it
Line large baking sheet with parchment paper. Place sweet potatoes on plate; microwave on high until tender, about 5 minutes per side. Cut in half and cool. Scrape sweet potato flesh into medium bowl and mash; transfer 3 cups to large bowl. Add ricotta cheese; blend well. Add Parmesan cheese, brown sugar, 2 teaspoons salt, and nutmeg; mash to blend. Mix in flour, about 1/2 cup at a time, until soft dough forms.
Turn dough out onto floured surface; divide into 6 equal pieces. Rolling between palms and floured work surface, form each piece into 20-inch-long rope (about 1 inch in diameter), sprinkling with flour as needed if sticky. Cut each rope into 20 pieces. Roll each piece over tines of fork to indent. Transfer to baking sheet.
Bring large pot of water to boil; add 2 tablespoons salt and return to boil. Working in batches, boil gnocchi until tender, 5 to 6 minutes. Transfer gnocchi to clean rimmed baking sheet. Cool completely. (Can be made 4 hours ahead. Let stand at room temperature.)
Preheat oven to 300°F. Melt butter in heavy large saucepan over medium-high heat. Cook until butter solids are brown and have toasty aroma, swirling pan occasionally, about 5 minutes.
(Reserve ¼ cup of the melted butter, Add 2 teaspoons brown sugar and 1/8 tsp cinnamon to ¼ cup of the melted butter, add half of this mixture to the last minute of sautéing of each batch.)
Transfer half of remaining butter to large skillet set over medium-high heat. Add half of gnocchi. Sauté until gnocchi are heated through, about 6 minutes. Empty skillet onto rimmed baking sheet; place in oven to keep warm. Repeat with remaining butter and gnocchi.
Cover with foil and return baking sheet to oven until ready to serve.
Divide gnocchi and sauce among shallow bowls. Sprinkle with chopped pecans.