https://beerandbrewing.com/recipe-mika-laitinen-s-sahti/
Toast 1 pound of rye
other 2 pounds leave malted
Toast rye
DIRECTIONS
Mill the grains, mix in the juniper branches, and mash at 140°F (60°C) for 45 minutes. Raise the mash to 158°F (70°C) for 45 minutes, then to 176°F (80°C) for 15 minutes. Recirculate until the wort runs clear, then run off into the kettle. Sparge and top up as necessary to get about 5–5.5 gallons (19–21 liters) of wort. Do not boil; instead, cool to fermentation temperature. For kveik and Lithuanian yeast, that would be 86–104°F (30–40°C); for baker’s yeast, about 64–77°F (18–25°C). Ferment until it begins to calm down—this can take 1–3 days. When the gravity has dropped to around 1.034–1.036—or when the sahti still tastes sweetish but not cloying—crash and cold-condition for 7–10 days. Rack to kegs or serving containers, and release the pressure occasionally, if necessary. The sahti is ready to drink 10–14 days after brewing, as soon as most of the yeast have settled. It is best enjoyed fresh and still, or very lightly carbonated.