Step 1

Bring 6 quarts water to boil and add 2 tablespoons salt.

Step 2

In a 12- to 14-inch saute pan, heat butter until foam subsides, add onion and cook until soft and golden-brown, about 7 to 8 minutes. Remove pan from heat and allow to cool. Add ricotta, Fontina, goat cheese, marjoram, parsley and nutmeg and season with salt and pepper.

Step 3

To form agnolotti, cut 3-inch strips of pasta lengthwise and place 1 tablespoon cheese filling 3 inches apart. Fold top of pasta down to bottom and pinch closed. Press dough flat between lumps of filling. Using a pastry cutter, cut half moons using folded part as flat side of moon. Continue until pasta and filling are finished.

Step 4

When all agnolotti are finished, drop into boiling water and lower heat. Cook at high simmer until tender. Meanwhile, melt butter with mushrooms in a 12- to 14-inch saute pan. Drain agnolotti and place in pan. Sprinkle with Parmigiano and toss over medium heat to coat. Serve immediately.

Step 5

This recipe yields 4 servings.