Melt butter in a large skillet, add sage leaves and sauté on medium-low until leaves are crispy and butter is just beginning to brown. Remove sage leaves and reserve.
Add in garlic, shallot, and red pepper flakes. Saute for 2-3 minutes until shallot is tender and fragrant. Add in shrimp and toss until shrimp turn pink, 3-4 minutes.
Toss in chopped parsley and crispy sage leaves.
Serve with forks or over cooked pasta.