Cook 4 oz. fresh cheese tortellini (about 1 heaping cup) in a large pot of boiling salted water, stirring occasionally, until very al dente, about 2 minutes less than package directions.
Meanwhile, cook 2 Tbsp. unsalted butter, cut into pieces, in a medium skillet over medium heat until golden brown and nutty smelling, 2–3 minutes (watch carefully).
Remove from heat and stir in 2 garlic cloves, finely chopped, a pinch of salt, and several grinds of freshly ground pepper.
Using a mesh sieve, scoop tortellini out of cooking liquid and transfer to skillet with brown butter sauce.
Set over low heat and toss to coat, adding a splash or two of pasta cooking liquid if you’d like a looser sauce.
Stir in ¼ cup chopped dill and juice of ½ lemon.
Transfer pasta to a shallow bowl and top with zest of ½ lemon; season with flaky sea salt and more pepper.
