Drain the vegetable mixture and let it drain. Peel and finely chop the onion. Wash the sage and dab dry. Pluck leaves from the stems. Cut half of the sage finely. Heat oil in a pan.
Fry the minced meat until crumbly, add the onion and cook over medium heat for about 5 minutes. Season with salt, pepper and chili. Let the minced meat drip off. Unroll puff pastry and remove baking paper. Cut off approx. 6 cm from the narrow side and press down on the long side so that almost a square is formed.
Place the puff pastry in a greased tart tin (approx. 22 cm Ø), dust with flour, cut the pastry all around, but leave the edges to overlap slightly. Sprinkle the dough with breadcrumbs. Mix the minced mass with vegetables, 175 g cheese and chopped sage and place on the puff pastry.
Wash, clean and slice the tomatoes. Cover the chopped tart with tomato slices and sage leaves, except for a few for garnishing. Sprinkle with 75 g cheese. Crumble tortilla chips over it. Bake in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: level 2) for about 20 minutes.
Remove from the oven and garnish with sage.