Put the raw almonds in a large glass, ceramic, or stainless-steel bowl. Add the homemade whey, then enough warm filtered water to cover the almonds by about 2 inches. Stir and cover loosely with a plate or clean kitchen towel.

Leave at room temperature for 24 hours. The almonds should become plump and the liquid may look cloudy and smell mildly cultured. Discard a batch with colored fuzz, a rotten odor, or other obvious spoilage.

Drain the almonds in a stainless-steel colander. Rinse with fresh filtered water if a milder flavor is desired. Shake the colander and drain until there is no steady drip.

For the finest result, peel the almonds by squeezing each one gently between two fingers until the skin slips off. Keep the peeled almonds in the colander.

Drain again and blot surface droplets with a clean lint-free towel. The almonds should feel plump and damp without leaving water in your palm.

Fit the Ninja BN801 food-processing bowl with its chopping blade. Add the almonds and pulse in one-second bursts for about 60 seconds total, stopping every 15 to 20 seconds to scrape the sides. Stop when the mixture is a pale, moist, evenly ground crumb before it turns shiny or pasty.

Use promptly in a recipe written for fresh fermented whole-nut flour. If the next batter is not ready, transfer the flour to a clean covered glass container and refrigerate immediately.