In a sauté pan, add the butter and the olive oil. When hot add the onion cook for one or two minutes. Add the shrimp and quickly sauté on both sides.
Add the garlic and when fragrant add the tomatoes and cook for a couple more minutes. Add the white vermouth and sherry.
Finish with a little more butter and prepare each plate with some polenta or fresh pasta in the middle and 6 to 8 shrimp per person depending on the size.
