Preheat oven 180C, line a baking tray with baking paper. Make a batch of the marzipan, set aside. Place all your fruit mix together to steep while you make the bread batter. In a food processor add the eggs & blitz them till they are pale & frothy for a couple of mins, before adding the rest of the wet ingredients, butter, yoghurt, almond extract, blitz to combine. Now add the rest of the dry ingredients, almond flour, coconut flour, xanthan gum, baking powder, salt & all spice. Mix well then tip this mixture onto the soaked fruit mix & fold together with a spatula. Place this bowl in the fridge to chill to firm up slightly. Dollop the dough onto the prepared tray use another piece of baking paper on top to press out a rectangle shape. Roll the marzipan out to the same length & place down the middle of the stollen dough. You are now going to use the baking paper & fold the dough over to create the shape & sealing in the sides. Use wet hands to prevent sticking. Scrape off any excess batter with a blunt knife & pop it on the dough. Bake for 20 minutes, then cover the stollen with tin foil top prevent it getting too brown & then bake for a further 20 minutes, test the bread is cooked with a skewer that comes out clean. Remove from the oven & brush with melted butter while warm & dust with powdered sweetener. Let cool completely before cutting. You can re-dust it more before serving if desired. Store in an airtight container for up to a week or freeze for 3 months.