Completely peel and devein the medium to large shrimp. Butterfly them generously to devein. This helps give them their "ear" shape.
Tuck a small peeled and deveined shrimp into curve of each larger shrimp. Skewer them both together with a toothpick. Refrigerate until ready to cook.
Melt the butter and olive oil together in a large saute pan. Add the garlic and red pepper and cook over low heat until garlic is very tender, about 15 minutes. Don't let it burn or brown!
Add rosemary. Cook 2-3 minutes more.
Salt and pepper the shrimp to taste and add them to the pan. You may need to do this in stages. Cook 2-3 minutes per side, until pink and cooked through. Sprinkle with lemon juice to taste and keep warm (if desired-- they're also good cold) until ready to serve.
To make this dairy-free, just skip the butter and double the olive oil.