Preheat the oven to 180C/350F/Gas Mark 4 and prepare your baking tin by greasing it lightly and lining the bottom with some baking paper.
Put flour, ground almonds, baking powder, baking soda and lemon zest (if using) in a large bowl and give them a good mix. I tend to use a small baloon whisk here to imitate sifting.
In another large bowl mix together all your wet ingredients (oat milk, yogurt, oil, vinegar) and caster sugar (yes, it does belong to wet ingredients). Make sure you give it all a good mix until all of the ingredients all really well combined.
Add dry ingredients into the bowl with wet ingredients and mix in gently only until just combined. It is important not to overmix your batter here.
Pour the cake batter into the prepared baking tin and very gently distribute your fresh raspberries on top of the batter, pushing them ever so slightly into it.
Next, sprinkle over some flaked almonds and quickly put your cake in the oven. Bake it 30-40 minutes until the skewer inserted into centre comes out clean.
Once baked, let the cake sit in a tin for 10-15 minutes before taking it out onto the cooling rack to cool completely.