Butter the cut side of each half of the brioche buns and toast them.
Make the hamburger patties by combining beef, pork sausage, fennel seeds, salt, and pepper. Shape into patties. Cook in a large non-stick skillet, just to brown. Remove patties from skillet.
Add brown sugar and maple syrup to the skillet and stir until sugar has melted. Replace the patties in the skillet. Cook a few minutes. Flip. Use a spoon to pour some of the glaze on top. Place shredded Colby on top and let melt. Place one patty on each brioche bottom.
Cook the peameal bacon. Remove from the pan and place one on each hamburger patty. Top with slices of red onion. Top with fanned out avocado slices.
Cook the eggs to over-easy. Place on top of the peameal. Place the top of the brioche bun on top.