Rinse the shells under cold water and sort them.
Saute the shallot in the olive oil. Add the diced tomatoes and garlic and deglaze with the white wine.
Then put the shells in the pan, put the lid on and bring it to the boil.
When the shells open, shake the pan briefly.
Turn off the heat under the pan and drain into a bowl to save the liquid for the sauce.
Cook the sauce in a saucepan and stir in the beurre manie until the sauce is thick. Add some cream if necessary.
Put the cooked pasta in the sauce and add the shells as well.
Sprinkle over the sea lavender, parsley and cayenne pepper and stir to combine. Serve hot.