Preheat the oven.Preheat oven to 400°F. Line a sheet pan with parchment paper.
Mix the meatloaf.In a large bowl, combine the ground turkey, Italian sausage, egg, breadcrumbs, flaxseed, Worcestershire sauce, BBQ sauce, Italian seasoning, garlic powder, onion powder, black pepper, and salt. Mix until just combined. Do not over mix.
Shape on the sheet pan.Press the mixture onto the prepared sheet pan into an even rectangle, about 3/4 to 1 inch thick. Shape it so it will be easy to slice into portions that fit sub rolls.
Add the glaze.Spread or brush the BBQ sauce evenly over the top.
Bake.Bake for 20 to 25 minutes, or until the meat is cooked through and reaches 165°F internally.
Broil for color, optional.For more caramelization on top, broil for 1 to 2 minutes at the end, watching closely.
Rest and slice.Let the meatloaf rest for 5 minutes before slicing.
Serve.Serve as is, or place slices in toasted sub rolls with cheese, lettuce or slaw, and pickles.