Peel onion and garlic. Chop the onion finely, press the garlic through a press. Clean the chilli, cut lengthwise, remove seeds, wash and chop finely. Mix oil, garlic, chilli and half the onion.
Dab steaks dry, place on a deep plate, brush with seasoning oil and marinate covered for approx. 1 hour.
Wash the tomatoes, dab dry and cut into slices. Wash lettuce and spin dry. Mix salad cream, yoghurt and remaining onion. Season with salt and pepper.
Cut the baguette into 4 pieces and cut each piece horizontally. Roast the baguette pieces briefly on the hot grill, let them cool down a little. Spread bread slices thinly with yoghurt cream.
Pat minute steaks dry and grill them on the hot grill for 1-2 minutes on each side. Season steaks with salt and pepper. Cover lower baguette halves with lettuce, steaks and tomato slices. Spread the rest of the yoghurt cream on top.
Season with pepper. Place the upper baguette halves on top and serve immediately.