Grind the linseed/flaxseed and the caraway seeds until powdered. Add to a small bowl and mix in the remaining ingredients. Stir until well combined.
Pour the ½ the chaffle ingredients onto the chaffle maker and gently spread out to cover the base. Cook until the chaffle is cooked through and has browned. Remove gently onto a serving dish and cook the remaining half of the batter.
To Make a Reuben Sandwich
Place sliced corned beef and Swiss cheese onto one of the chaffles. If you want melted cheese, zap for 30 seconds in the microwave. Top with sauerkraut and a generous drizzling of easy to make Keto Reuben Russian Dressing To make your own corned beef/silverside, check out this simple recipe for Keto Corned Beef.
Note that if you use Mozzarella cheese your chaffle is more likely to spread over the sides of your chaffle maker. My preference is to use a hard cheese as it prevents this from happening although Mozzarella cheese creates a softer rye bread.