Preheat the oven to 200°C (400°F).
Prepare two ramekins by greasing them with a little butter. Then, dust each with about 1 tablespoon of cocoa powder, making sure to coat the sides and bottom well. This helps the cakes release easily after baking.
In a large bowl sift all the dry ingredients, flour, cacao powder, baking powder and sugar. Give everything a quick whisk to combine.
Add milk and vegetable oil and whisk all together until you have a smooth chocolate cake batter.
For easy pouring, transfer the batter to a measuring cup or jug. Then evenly pour the batter into the prepared ramekins.
Place the ramekins on a baking tray for easier handling and transfer them to the middle rack of your preheated oven.
Bake at 200°C (400°F) for 15 minutes, or until the edges are set but the center is still soft.
Remove from the oven and carefully invert each ramekin onto a serving plate.
Let them sit for a few seconds before lifting the ramekin off to reveal the lava cake.
Serve warm for a gooey, molten center or let it cool slightly for a firmer, more stable texture.