Preheat oven to 350F. First we are going to make our flax egg and let it set. Combine 3 tbsp ground flax, 6 tbsp water, mix and let it sit for about 10 minutes.
Take your 1 1/2 cup of oats and gently pulse in blender to make oat flour.
Next combine your lentils, water, and the rest of the ingredients (except for the oats, seasonings and ketchup) in a large sauce pan. Bring to a boil, cover, reduce the heat to a simmer and let cook about 30 minutes or until the majority of the water is absorbed.
Remove from heat, add in flax egg and seasonings, then slowly add in oats until you get a thick consistency.
Transfer mix to a non stick loaf pan and place in the oven on the middle rack for 30 minutes uncovered.
Remove from the oven, spread a thin layer of ketchup over the top of the loaf and place back in oven uncovered for 15 minutes or until the ketchup caramelizes. Let rest for 30 minutes before serving. Slice and enjoy.