1. Warm your oven to 180°C/Fan 160°C/Gas 4. Grease a 20cm x 26cm baking tin with sunflower spread and line it with baking paper.
2. Spoon the ground flaxseeds into a small bowl and add the oat milk and 1 tbsp vanilla extract. Stir well to combine and set aside. Finely chop the dates and slide them into a separate small, heatproof bowl. Pour over the hot espresso and stir well to combine. Leave both bowls to soak for 10 mins.
3. Fill a pan with water till it's about one-third full. Pop it on the hob and bring to a simmer. Break the milk chocolate into small chunks and slide it into a heatproof bowl (one large enough to sit on top of the pan). Add the sunflower vegetable spread to the chocolate, along with the golden syrup.
4. Put the heatproof bowl over the simmering water, making sure that the bottom of the bowl is not touching the water. Turn the heat down to very low. Melt the chocolate, vegetable spread and syrup together, stirring frequently, till smooth and fully combined. Remove the bowl from the heat and set aside to cool a little.
5. Tip the flour into a large bowl and add the ground almonds, 1 tsp baking powder and ½ tsp bicarbonate of soda. Whisk to mix the dry ingredients together. Set aside.
6. Tip the raw cane sugar and rapadura/sucanat wholecane sugar into a seperate large mixing bowl and add a good pinch of salt. Pour in the melted chocolate and beat to combine.
7. Scoop in the soaked flaxseeds and the dates, with any liquid from their bowls, and stir well again. Finally, fold in the dry ingredients till just combined.
8. Scoop the batter into the lined baking tin and smooth out with a spoon. Slide the tin into the oven and bake for 25-35 mins, till set on top with a slight wobble in the middle. Set aside to cool in the tin.
9. Once cooled, turn the brownies out of the tin, slice into 9-12 brownies and serve. The brownies will keep in an airtight tin for around a week or can be frozen for up to 3 months.