Spread 1 side of each bread slice generously with mayonnaise mixture. Layer cheese, bell pepper strips, ham, basil, and lettuce on half of bread slices. Top with remaining bread slices, mayonnaise mixture sides down. Cut sandwiches in half.
This was so delicious -- perfect for a summer lunch or light dinner with a salad. My son-in-law said it was as good as anything he'd had in a restaurant. The only changes I made were to use roasted red peppers instead of raw, because some of us can't eat raw pepper, and to use ciabatta instead of sourdough. The fontina was so rich and creamy!
I served this in a picnic lunch to my book club, it was wonderful! I used a hard crust flat bread, and used havarti thin sliced cheese since fontina can't be sliced thinly. The pesto mayonnaise made it!
Everyone asked for the recipe....