Creamy Pasta With Salmon and Asparagus

dried bow tie pasta, or farfalle

chopped asparagus spears, cut into 1-inch pieces

heavy cream

Zest of 2 Meyer lemons (use 2-3 regular lemons if you can't find Meyer lemons)

freshly grated Parmesan cheese

chopped fresh dill fronds, plus more for garnish

flaked, cooked salmon

kosher salt and freshly ground pepper