"They are, *chef's kiss*, everything...."
Cooking spray
(8-oz.) tubes crescent roll dough
butter, divided
medium onion, thinly sliced
sprigs fresh thyme, divided
Kosher salt
Freshly ground black pepper
grainy mustard
deli roast beef
slices provolone
freshly chopped parsley
clove garlic, minced
beef stock
Worcestershire sauce