Bring 3-4 l salted water to the boil in a large pot. Wash the tomatoes. Peel and finely dice the shallots. Wash sage and shake dry. Pluck off the leaves, cut larger ones 1-2 times.
Pour the spaghetti into the boiling water and press it down so that all the noodles are in the water. Cook for 8-10 minutes, stirring from time to time to prevent them from sticking together.
In the meantime, roughly chop the nuts. Roast in a pan without fat. Stir more often, as the nuts burn easily. Stir the butter into pieces at low heat and let it melt.
Stir the shallots and sage into the nuts and steam briefly. Steam the tomatoes for about 3 minutes. They should burst open a little, but not become too mushy. Season to taste with salt and pepper.
Slice thin shavings off the Parmesan cheese with a peeler. Take out a pasta and try if it is "al dente", i.e. cooked, but still has bite.
Then drain the pasta and pour it back into the pot. Add nut butter immediately and mix everything well. Arrange on plates and sprinkle with the Parmesan shavings.