Grease and line the base and sides of a 20cm (8”) loose-bottomed round cake tin with vegan margarine and baking paper.
Sprinkle the light and dark brown sugars evenly across the base of the tin.
To prepare the pineapple, slice off the top and bottom, then trim around the sides to remove the skin. Slice the pineapple into seven 1cm (1/2”) thick rings. Trim the outer edges of each ring so they fit comfortably in the tin.
Use a small knife to cut a hole in the centre of each slice, large enough to fit a glacé cherry. Store any leftover pineapple in an airtight container in the fridge (see tips).
Pat the pineapple slices dry with a clean tea towel or paper towel to remove excess moisture.
Arrange the pineapple slices across the sugar-lined base of the tin, then place a glacé cherry in each centre. Use any remaining cherries to fill small gaps around the edges.
Preheat the oven to 180°C fan / 200°C / 400°F.
To make the cake batter, whisk together the light brown sugar, vegan margarine, and the zest of 2 lemons in a large bowl until smooth.
In a jug, combine the soy milk with the juice from all 3 lemons. Stir and set aside for 2-3 minutes until it forms vegan buttermilk.
Add the flour and baking powder to the mixing bowl and stir until the mixture resembles a coarse crumb.
Pour in the vegan buttermilk and vanilla extract. Stir until just combined, being careful not to overmix.
Spoon the batter over the pineapple layer and level the top with a spatula.
Bake for 45-50 minutes, or until a toothpick inserted into the centre comes out clean.
Leave the cake to rest in the tin for 15 minutes. Then turn it out onto a serving plate and gently peel away the baking paper. If you like, once the cake is turned out, brush the pineapple lightly with a little maple syrup to give it a glossy finish.
Serve warm with vegan vanilla ice cream.