Cook ground sausage; set aside to cool slightly.

In large bowl, combine ricotta cheese, bread crumbs, egg white, oregano, garlic powder, thyme, basil, black pepper, red pepper flakes (optional) and shredded Italian cheese. Add cooked sausage; mix well. Set aside.

Lay a beef strip on work surface. Starting at the wide side, cover with 5 slices of sandwich pepperoni, extending beyond the edges of the beef slice. Lay both halves of a provolone slice on top. Scoop 3 tablespoons of cheese mixture on top of cheese slices, spreading evenly over the top but maintaining a 1 1/2-inch border from edge.

Beginning at thin tip, roll up the beef strip, tucking pepperoni edges inside as you roll (to prevent filling from leaking out). Secure with two skewers. Repeat for remaining beef strips.

Pour marinara sauce and tomato sauce into slow cooker. Lay meat rolls over the sauce. Cook on low for 4-5 hours.