Add the orecchiette and stir well during the first few minutes so the little ears don’t nest inside one another.
Cook until the pasta is about 1 minute short of your preferred texture.
Don’t rely entirely on the package directions. Taste several pieces, paying particular attention to the thicker centers.
Before draining, reserve at least 1½ cups of the pasta water.
Drain the pasta.
6. Bring everything together
Add the orecchiette to the pan with the sausage, fennel and mushrooms.
Begin tossing immediately.
Add the reserved pasta water a little at a time until the sauce becomes glossy and begins clinging to the pasta.
The starch in the pasta water emulsifies the sausage fat, butter, stock and cheese into a silky coating.
No cream is necessary.
7. Finish the dish
Remove the pan from the heat.
Add the Parmigiano Reggiano, Pecorino Romano, the remaining 2 tablespoons of butter, lemon zest and chopped fennel fronds.
Toss until the cheese has melted and the sauce coats every piece of pasta. Add another splash of pasta water if the sauce becomes too tight.
Taste before adding salt. The sausage, stock and Pecorino may already provide all the seasoning the dish needs.
Finish with plenty of freshly ground black pepper.
Serve with another shower of Parmigiano Reggiano, a drizzle of excellent olive oil and chopped parsley, if desired.
A crisp Vermentino or Pinot Grigio would be very much at home alongside it.
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