Preparation Simmer stock with dill stems in a 4- to 5-quart saucepan, uncovered, until reduced to about 8 cups, 25 to 30 minutes. Discard dill stems. Add asparagus and peas, then bring to a boil, partially covered. Reduce heat and simmer, uncovered, until asparagus is crisp-tender, about 3 minutes. Stir in dill leaves and season with salt and pepper.
Preparation Simmer stock with dill stems in a 4- to 5-quart saucepan, uncovered, until reduced to about 8 cups, 25 to 30 minutes. Discard dill stems. Add asparagus and peas, then bring to a boil, partially covered. Reduce heat and simmer, uncovered, until asparagus is crisp-tender, about 3 minutes. Stir in dill leaves and season with salt and pepper.