Preheat your oven to 350ºF. Spread the almonds in an even layer on a rimmed baking sheet. Roast the almonds for 10-15 minutes, until fragrant and golden brown.
While the almonds are still hot, add them to your food processor along with the salt. Blend for 20-25 minutes, scraping down the bowl and lid with a spatula if the clumps get stuck.
Will keep in a pint mason jar for 2 weeks at room temperature, or at least 2 months refrigerated.