Mix the crab, mayo, celery, green pepper, onion, parsley, lemon, tabasco and cayenne in a medium sized bowl, taste and add salt and pepper if desired.
Refrigerate for 1 hour, (this could be done a day in advance of baking)
Preheat oven to 400° F
Put bread cubes in food processor and pulse until finely chopped.
Spread crumbs on a rimmed baking sheet and toast for 6 to 8 minutes until just starting to brown.
Melt butter in a large skillet on moderate heat and let the milk solids brown, about 4 minutes
Add the bread crumbs to the butter and stir to evenly coat, lightly salt
Pour the crab mixture into a shallow 1.5 quart baking dish
Sprinkle with bread crumbs
Bake for 20 to 25 minutes, until browned
Let cool 5 minutes
Serve with crostini or radicchio leaves