Mayo with Parmesan cheese, garlic and basil. Chopped tomatoes and scallions. Here's the "official" measurements but I don't go by it.
1/4 cup fresh basil (I use dried)
1/4 cup Parmesan cheese
1 med clove garlic, minced
3 T mayo
12 slices French bread
4 teasp chopped maters
1 green onion with top, chopped