Step 1

Melt butter in a large straight-sided skillet or wide, shallow pot over medium-high heat. Add scallion white and light-green parts, onion, peppers, celery, and thyme; season with salt and pepper. Cook, stirring a few times, until vegetables are crisp-tender and golden in places, 6 to 8 minutes.

Step 2

Stir in corn kernels and milk, then vermouth; boil until liquid has mostly evaporated, about 1 minute. Stir in stock, cream, and shrimp. Bring to a simmer (but do not let boil), reducing heat as necessary, and cook until shrimp are opaque and just cooked through, 2 to 3 minutes. Remove from heat. Discard thyme sprigs, stir in dark-green scallion tops, and serve.