Preheat the oven to 180C/350F degrees and line a muffin tin with 8 liners.
Remove the seeds from the jalapenos and slice one of the jalapenos into 8 slices. The remaining jalapenos are to be chopped to be used in the muffin mixture.
In a medium bowl, add the coconut flour, lupin flour, baking powder, salt and black pepper.
Beat the eggs, sour cream and melted butter until combined.
Add the egg mixture to the dry ingredients and stir thoroughly.
Add the chopped jalapenos, cheddar cheese and water and stir until you have a smooth mixture. If the muffin mixture looks too stiff, add additional water or a splash of almond milk.
Spoon the muffin mixture into the muffin tin.
Place a jalapeno slice on top of each muffin and bake for 20-25 minutes until golden and firm.
Allow to cool for 5 minutes before removing from the tin.