Wash the peaches, half them, remove the pit, and cut into slices.
Preheat the oven to 360°F/180°C.
For the batter: In a mixing bowl, combine the flour, sugar, baking powder, and baking soda. Whisk. Add the oil, apple cider vinegar, and plant-based milk. Whisk again until it's a smooth batter.
For the crumb layer: Put the cold butter, all-purpose flour, and sugar in a bowl, mix and knead with your hands until crumbly.
Place parchment paper into the baking pan. Pour in the cake batter, place the peach slices on the cake batter and press them down a bit. Sprinkle the crumbs on top.
Bake the cake in the oven for about about 25 minutes. When the crumble is nice and golden, your cake should be ready.