Prepare dinner as directed on package.
Cook and stir onion and red pepper in 2 tablespoons of the butter in small skillet on medium-high heat until tender. Add to Dinner. Stir in crabmeat, peas
and mayo. Spoon into 1-1/2-quart casserole; cover.
Bake at 350 F for 15 minutes.
Melt remaining 2 tablespoons butter. Stir in crumbs and onion salt. Uncover casserole; top with crumb mixture. Continue baking, uncovered, 5 to 10 minutes or until golden brown and thoroughly heated.