Wondering what Lupin Flour is and how to use it? This guide explains the ins and outs of low carb Lupin Flour: what it is, where it comes from, and how to use it in Keto cooking. Lupin Flour has just one ingredient: Sweet Lupin Beans. It’s made entirely from plant protein so it’s Vegan, Raw, Grain-Free, and Gluten-Free compliant. It's got many uses in low carb baking and has more nutrients than white flour.