Mix buckwheat flour and hazelnuts with 200 g sunflower seeds, linseeds and 4 teaspoons of salt. Melt coconut oil in a small pot. Mix with 400 ml water and maple syrup. Stir into the dry ingredients with the dough hooks of the mixer.
Line an ovenproof dish (approx. 15 x 25 cm) with baking paper. Pour the dough into the baking dish and press down gently. Leave to rest for about 2 hours. In the meantime, soak 60 g sunflower seeds in water for about 2 hours.
Preheat oven (electric cooker: 180 °C/circulating air: 160 °C/gas: see manufacturer). Bake bread in a hot oven for 40-50 minutes. For the spread, put soaked sunflower seeds in a sieve and drain very well. Then roast in a pan without fat for about 3 minutes. Cut the beetroot into pieces. Finely puree with 4 tablespoons of water, sour cream, olive oil, vinegar and roasted sunflower seeds using a hand blender. Season to taste with salt and pepper.
Remove bread from the oven, let it cool completely, cut into slices. Cut cress from the bed as desired. Peel horseradish, grate finely. Sprinkle beetroot dip with cress and horseradish.
Tip: Linseed contains a lot of fibre. This will fill you up for extra long! But you should drink plenty of it, as it swells up after consumption.