Dissolve the bouillon cube in 2 tablespoons of boiling water and set aside to cool. Put the oatmeal into a blender and pulse to chop coarsely.
Place the oatmeal into a large bowl and add the remaining dry ingredients, wheat gluten through flax seeds, stirring well to distribute the seasonings evenly. Mix the bouillon mixture with the cool water in a large measuring cup or bowl and add the garlic, tahini, and soy sauce. Whisk or blend with a hand blender until ingredients are well-distributed.
Pour the wet ingredients into the dry, and stir to mix just until evenly moistened. Add a little more water if it seems too dry.
Place a piece of aluminum foil on the counter, and scoop 1/2 cup of gluten mixture onto it. Shape into a rough tube, fold the bottom edge of the foil over the gluten, and roll up. Roll the tube back and forth, pressing lightly with your hands, to give it an even shape, and then twist the ends closed. Repeat with the remaining gluten to form 5 sausages.
Place all the sausages in the top of a steamer, cover, and steam for 40 minutes. Remove them from the heat and let cool (refrigerating will make them firmer). Fauxsages can then be used in recipes as-is, but baking or pan-frying lightly will make them firmer and browner.