Season the chicken breast with salt and pepper, and drizzle it with the olive oil.
Cook it in a hot pan for 4 to 5 minutes per side, until golden brown and fully cooked through.
Let it rest for a few minutes, then cut it into thin strips.
Mash the avocado with a fork, then mix in the lemon juice, a pinch of salt, and the yogurt to get a creamy spread.
Briefly heat the tortillas in a dry pan or microwave so they can be rolled up easily.
Spread the avocado cream on the tortillas.
Place the salad leaves, tomato, chicken strips, and ham on top.
Roll them up tightly, then serve cut in half.