What do you need:

4 cups whole wheat flour
3.5 cups rye flour
2 tbsp. l. baking powder (baking powder)
1.5 st. l. baking soda
1 ч. l. salt
4 стакана пахты (можешь заменить 1 стаканом молока и 1 ст. l. лимонного сока)
1/2 cup cumin seeds
What to do:

Heat up the oven to 220°C. Grease a baking sheet with oil and sprinkle with a little flour.
In a large bowl, mix both flours, baking powder, baking soda and salt. While stirring thoroughly, pour in the buttermilk and add the cumin. The dough will be sticky, so use a wooden spatula to mix or dust your hands with flour while kneading.
Shape the dough into three loaves and place them on a baking sheet. Leave plenty of room between the loaves as the loaves will expand as they bake.
With a blade sprinkled with flour, make several symmetrical cuts on top of each loaf. Sprinkle the cuts with flour as well.
Bake for 50 minutes, or until the tops are golden brown and the bottoms of the loaves start to make a buzzing sound when tapped (as if the inside is empty).
Lay the rye bread out on a dry, clean surface and let cool.