Step 1

Place tuna, mayonnaise, lemon juice, salt and half of the chopped avocado in a food processor; process on High, scraping down the sides of the bowl as needed, until smooth and fluffy, about 1 minute. Stir in pepper. Transfer to a medium bowl; cover with plastic wrap and refrigerate until ready to use.

Step 2

Wash and dry the food processor bowl. Add pesto, chili crisp and the remaining half of the chopped avocado; process on High until smooth and creamy. Transfer to a small bowl.

Step 3

Arrange toast on a work surface. Spread 1 tablespoon of the pesto mixture on each slice. Spread 1/2 cup of the tuna mixture on each of 4 slices over the pesto layer. Evenly layer sliced avocado, tomato slices and lettuce on top of the tuna mixture; top with the remaining toast slices, pesto-side down. Cut the sandwiches into halves.