Step 1

1 Combine the feta and yogurt in a food processor; puree until smooth and creamy

Step 2

2 Transfer to a small bowl; season lightly with pepper

Step 3

3 Spread the mixture over each flatbread

Step 4

4 Arrange the cucumber, onion, tomato and avocado slices over one half of each flatbread

Step 5

5 Season lightly with salt and pepper, then top with the mint

Step 6

6 Finely grate some lemon zest over each portion, then cut the lemon in half and squeeze some of its juice (to taste) over each one

Step 7

7 Fold over to form a sandwich; use toothpicks as needed to hold the bread in place

Step 8

8 Cut the sandwiches in half if desired, and serve