Here's how you do it. Put the peppers whole in a pan and put it under your broiler at highest heat. Watch carefully and turn them as they start to wrinkle and darken. Keep turning until all sides are nearly black.
When they're done, flatten them and remove the seeds (saving the lovely juices for adding to a pasta sauce perhaps). Laurie suggested running them under cold water to rinse off the seeds and membranes so I did that.
I used some on these slices of zucchini that had been floured and cooked in good olive oil. Then I laid the pimientos on top and added a few slices of garlic clove, then a bit of oil. The garlic cloves are removed before serving, they are just to give an essence of garlic flavor. This was one of the nicest things I've ever eaten.
By the way, Laurie Colwin was a writer who loved food and words. She wrote several novels and collected stories but my favorites are her two collections of essays on cooking: Home Cooking and More Home Cooking. I have both these books and find her recipes simple and delicious. Sadly she died in 1992 when she was just in her 40s. Her books are still available.