Cook the macaroni in salted water until al dente. Drain, set aside.
Gently sauté the onion strips and the finely diced garlic cloves in a saucepan in olive oil without browning them. Take out of the pot and set aside.
Leave out the strips of bacon in the saucepan while the heat is not too high. Add the onions again.
Mix the crème fraîche, sour cream and whipped cream in a bowl, season with a little salt (not too much, the bacon is salty), freshly ground pepper and paprika, pour over the bacon and onions, bring to the boil briefly.
Fold in the macaroni and remove from the heat.
Pour the macaroni, bacon and onion mixture into a large baking dish, cover with the tomato slices. Sprinkle with grated cheese and bake in a preheated oven at 200 ° C top / bottom heat for 15 minutes.
Arrange on plates, sprinkle with some chives and serve.