Here is a recipe from one of the Frugal Gourmet's
cookbooks, I've tried it and it is very good. I even made it for our entire office - and it was a big hit!

OLIVE SALAD (To be made the day before you want to
serve it)
3 large garlic cloves, crushed
1 cup chopped pimento stuffed olives
1 cup pitted and chopped black ripe olives or calamatas
1/2 cup roasted sweet red peppers cut unto small chunks
1 cup olive oil
3 Tbsp. chopped fresh parsley
2 Tbsp. white wine vinegar
Mix all of the above and let stand overnight. Need not be
refrigerated for the first night.

MUFFALETTA FROM NEW ORLEANS
1 large round freshly baked italian loaf
1/3 pound salami, sliced thin (Genoa or Italian wine cured)
1/2 pound provolone cheese, sliced thin
1/2 pound mild cheese, such as Havarti, sliced
1/3 pound mortadella or prosciutto or coppa ham, sliced

Make the salad the day before. Cut the bread in half
horizontally, as you would for a sandwich. Scoop out some
of the center of the loaf and drizzle olive oil from the salad
on both halves of the bread. Use plenty! On the bottom half,
place the salami, olive salad, cheeses and mortadella. Top
with the other half of the loaf. Cut into wedges.