Clean, wash and spin dry the lettuce. Dice the mozzarella.
Fillet the orange, so cut off the lids at the top and bottom and just cut the peel around into the pulp so that the white skins no longer cover the chambers with the pulp. Cut out the fillets over a bowl and collect the juice in the bowl. Halve the pomegranate, add the seeds and juice directly to the bowl.
Then make the dressing from mustard, vinegar and oil and season with salt and pepper. Combine all ingredients and stir.