Pasta with "my" pesto

It's a simple but tasty recipe. Actually, it's a a new version of an Italian classic, that I simply adore: the pesto sauce from Genoa. I just changed the original recipe according to my own taste ( that's why I called it "my" pesto) and to the ingredients available ( in this case, Rosemary, since I always have a lot of it).

Ingredients
320g pasta (types: trofie, trenette, linguine)
2/3 branches of rosemary with its flowers
200g almonds
50g Parmesan
coarse salt
extra-virgin oil

Wash the rosemary and keep the flowers. Then put the rosemary in the mortar and with a pestle pound  it with the almonds, grinding carefully both ingredients, and pestle until smooth. Add some coarse salt. Then add the oil and blend all the ingredients. Once it is well mixed, add the Parmesan you had previously grated. Meanwhile cook the pasta in hot boiling water and drain it when it's "al dente". Add the pesto sauce and use the flowers as a decoration.