Shrimp Butter

In a skillet, caramelize onion, garlic cloves and thyme in unsalted butter. Toss in shrimp. Add anchovy fillets, lemon zest, nutmeg, cayenne and celery seed. Cook slowly until golden. Transfer to food processor and puree until smooth. With processor running add softened butter, 1T at a time. Force through fine-mesh strainer. Season with kosher salt and fresh pepper. Restrain if desired.

Onion 1, chopped
Garlic cloves 2 minced
Thyme 1 sprig fresh
Anchovy fillets 4 chopped
Lemon zest 1/2 tsp
Nutmeg 1/2 tsp
Celery Seeds pinch
Cayenne Pinch
Shrimp 1 pound, shell-on
Butter 2 sticks, unsalted, softened plus 1 T for onions