Cut zucchini lengthwise into 1/2 cm thick slices and saute in a pan in olive oil and water until soft. Lift out zucchini leaves and reserve the liquid.
To make the stuffing, seed the peppers, place on a baking sheet and bake in the oven with the broiler on for 5 minutes. Let cool briefly and peel off the skin. Cut into cubes and set half aside.
Sauté shallots in oil until translucent, add half of the diced peppers and deglaze with white wine. Add the mixed tomatoes, season with salt and cayenne pepper and steam for 5 minutes. Puree with a hand blender.
Spread this filling on the zucchini leaves and roll them up.
Brown butter in a saucepan and deglaze with the stock that was created when the zucchini slices were prepared. Warm the zucchini rolls and diced peppers in it, lift them out and arrange them with tarragon threads.