Preheat your oven to 425°F so it's hot when you're ready to bake.
Mix the softened butter, parsley, garlic, Worcestershire sauce, salt, and white pepper in a small bowl until everything comes together.
Spread out the parchment sheets and set one tilapia fillet on each.
Spoon a quarter of your seasoned butter onto each fillet and spread it over the top.
Lay a few lemon slices on each piece of tilapia for some bright flavor.
Fold the parchment over the fish and twist or crimp the edges to seal, making sure steam can't escape while it bakes.
Set the packets on a baking sheet and bake in the middle of the oven for 12 to 15 minutes, until the fish flakes easily with a fork.