Chop the rosemary needles and mix about 2 teaspoons with the sour cream. Preheat the oven to 225 ° C.
Place the tarte flambée batter, homemade or from the cooling shelf, on a baking sheet with baking paper and brush with the rosemary sour cream. Leave about 1 cm free all around.
Peel and finely slice the beetroot, cut the white parts of the spring onions into fine rings (alternatively the onion into fine wedges), cut the chorizo into fine slices and possibly halve or quarter, coarsely chop the walnuts and crumble the feta cheese. Distribute the ingredients in sequence on the pastry plate and drizzle with a little honey if you like.
Bake in the preheated oven for approx. 15 minutes until the desired brown color. The baking time can vary slightly depending on the oven.