Cut one iceberg lettuce into half. Gently separate the layers of leaves.
Now, slice two avocados. Remove the pits and scoop out the flesh.
Cut six cherry tomatoes into thin slices. You can add more than six cherry tomatoes to your keto salad sandwiches.
Lay out four lettuce leaves and spread a thin layer (or 1 tsp) of mayonnaise on each. Then, slices of avocado, cheddar cheese, and cherry tomatoes. Serve.