Tip the flour, cocoa powder, baking powder and sugar into a large bowl with a small pinch of salt. Add the eggs and whisk until smooth. Gradually whisk in the milk until you have a smooth batter, then mix in the chocolate chips.
Heat a splash of the oil and a little of the butter in a non-stick frying pan until sizzling. Cook the pancakes, using 2 tbsp batter for each, for 2 mins until bubbles start to form on the surface. Flip and cook for 2 mins more (you'll need to do this in batches). Keep the pancakes warm in a low oven while you cook.
To serve, whip the cream with the icing sugar and vanilla until thick. Top the pancakes with the whipped cream, berries and maple syrup, if using.