Whisk eggs, milk, banana, vanilla extract, and coconut oil together in a large bowl. Add ground flaxseeds, chia seeds, cinnamon, and collagen, and box mix until well-blended.
Pour batter into lightly greased (or parchment paper covered) 8-by-4-inch loaf tin.
Bake for 30 minutes.
Then, cover loosely with foil; bake an additional 25 to 30 minutes or until a toothpick comes out clean and edges of loaf start to pull away from the pan.