Put a splash of cooking oil in pan and add the onion and bell pepper to it. Salt and pepper the veggies and saute until soft. In another pot, put water on to boil for the pasta. Use cold water. Add salt to the water when it gets hot.
Into the pot with the onion and bell pepper, stir in the mushroom soup, the heavy cream, the sherry and the brocoli. Let mixture cook briefly.
Add the crabmeat. Mix together the egg yolk and the milk and add to the mixture. After a few minutes, add the parmigiana cheese. When it has melted into the mixture, check seasoning and adjust. By now the pasta water should be boiling, so add it to the pot. I used capellini (angel hair),which cooks very fast, but you can use spaghetti, fettucini or whatever you choose.
Drain the pasta, toss it with the crab mix and serve.