1. Begin by combining yeast, salt, and 30 milliliters (2 tablespoons) of cold water in a small bowl. Stir gently to dissolve the yeast, then let it sit for 5-7 minutes, or until it becomes frothy.

2. In a large mixing bowl, combine 250 grams (2 3/4 cups) all-purpose flour, 120 grams (1 1/2 cups) whole wheat flour, and 120 grams (1 cup) chopped walnuts.

3. Add 20 grams (1 tablespoon) honey, yeast mixture, and 400 milliliters (1 3/4 cups) remaining cold water to the dry ingredients. Mix until a shaggy dough forms.

4. Knead the dough on a floured surface for 10-12 minutes, until it becomes smooth and elastic.

5. Place the dough in a greased bowl, cover it with a damp cloth, and let it rise in a warm place for 1-2 hours, or until doubled in size.

6. Preheat your oven to 190°C (375°F). Punch down the dough and shape it into a round or oblong loaf.

7. Place the loaf on a baking sheet lined with parchment paper, cover it with a clean towel, and let it rise for another 30-40 minutes.

8. Bake the bread for 35-40 minutes, or until golden brown. Let it cool on a wire rack for at least 10-15 minutes before slicing and serving.