In a small bowl and using a large fork, coarsely mash avocado. Add mayonnaise, 2 teaspoons lemon juice, salt, and pepper, stirring and mashing until combined and creamy. Pack aïoli into a container and sprinkle top of aïoli with remaining 1 teaspoon lemon juice. Cover surface of aïoli with a sheet of plastic wrap, cover container, and refrigerate for a few hours until needed.
Recipe by TeaTime Magazine at https://teatimemagazine.com/pastrami-avocado-tea-sandwiches/