Jul 26, 2016· Attach the Mockmill Grain Mill to your KitchenAid mixer. Set it to the finest setting. Place your toasted lentils in the hopper. Turn on the mixer and grind the lentils. Sift the lentil flour through a fine sieve into a bowl or container. You can send any pieces of lentils that are too large to pass through the sieve back through the grinder.