Step 1

If using fresh peas: Fill a large saucepan half full with water and 2 tsp kosher salt and bring to a boil. Drop the peas into the boiling water and cook until just tender (taste one or two), 2 minutes for smaller peas, 3 minutes for larger, older peas. Begin timing immediately; don’t wait for the water to return to a boil. Use a mesh strainer to transfer the peas to a dish towel or a few layers of paper towels to drain. Discard the water the peas were boiled in, but reserve the pot.

Step 2

If using frozen peas: Put them in a colander and run cold water over them for a few minutes until they’re mostly thawed. Spread them out on a few layers of dish towels to drain

Step 3

Melt the butter in the reserved saucepan over low heat. Add the scallions and sauté until softened, about 3 minutes. Add the heavy cream, half of the mint, the lemon zest, 1/4 tsp of salt, and a few grinds of pepper. Bring the mixture to a boil and cook until it thickens slightly and a wooden spoon leaves a wide path when scraped across the bottom of the pan, about 1 minute. Add the peas and stir until they’re heated through and well coated with the sauce, 1 minute more. Remove the pan from the heat, taste for salt and pepper, and serve immediately, garnished with the remaining mint.