To begin, warm the buttermilk gently until lukewarm and combine it with warm water in a large mixing bowl. Sprinkle in the yeast and let it sit for 10 minutes until slightly foamy, which ensures the yeast is active and ready to ferment the dough.

Whisk in the molasses and honey until fully dissolved. Stir in the salt and optional ground caraway for a classic aroma. These ingredients not only deepen flavour but help balance the tangy profile of rye.

Gradually mix in the rye and whole wheat flours. Use a wooden spoon or dough hook on a mixer to form a thick, sticky dough. Avoid over-kneading; rye lacks gluten, so mixing too much makes the bread heavy rather than springy.

Lightly oil a medium bowl and transfer the dough into it. Cover tightly with a clean cloth or cling film and let it rest at room temperature for 12 to 18 hours. This slow fermentation builds the bread’s signature sour and slightly sweet complexity.

After resting, the dough should have risen slightly and show small air pockets. Lightly flour a work surface with rye flour and shape the dough into a rounded loaf. Handle it gently to preserve the fermentation bubbles within.

Grease a loaf tin or baking tray and place the shaped dough inside. Cover and allow to rise again for 45 to 60 minutes in a warm area until slightly puffed. This second proof creates a more tender crumb and prevents the loaf from cracking.

Preheat your oven to 190°C (fan 170°C). Place a shallow pan of hot water on the lower oven rack to generate steam, which helps develop a firm but elastic crust. Let the oven heat for at least 20 minutes before baking.

Dust the top of the loaf lightly with rye flour. Score one or two shallow cuts across the top to guide expansion. Place the loaf in the middle rack and bake for 50 to 60 minutes, until deep brown and hollow-sounding when tapped underneath.

Remove the bread from the oven and let it cool on a wire rack for at least two hours. This resting period is essential, as the crumb continues to settle and moisture redistributes. Cutting too soon will cause the loaf to crumble.

Serve sliced with butter, cheese or smoked fish. For a more traditional pairing, enjoy it with caraway cheese or sour cream. To elevate the presentation, wrap the loaf in a linen cloth before slicing at the table.