Heat 300ml of the milk in a pan until it just starts to bubble around the edges, then leave it to cool until it is tepid.
Measure out the flour and then put 3 tbsp back into the bag. Add the cocoa, yeast and sugar and then stir the milk in, a little at a time, until you have made a smooth batter. Cover and leave to rise in a warm place for 1hr-1hr 30 mins or until doubled in size and very bubbly. Stir in a little more milk if the batter is very thick, if it is too thick the bubbles won’t rise to the surface as well.
When risen, add the remaining 50ml milk to the batter to let it down a little, then heat the grill to high. Lightly oil the insides of 4 x 9cm metal crumpet rings or metal cooks’ rings. Heat a large non-stick frying pan or griddle pan over a low-medium heat, add 1 tbsp oil and put the rings in the pan. Spoon the batter into the rings until they are half full. Let the crumpets cook slowly for about 10 mins or until the mixture has set and the bubbles on top have all popped. Lift the rings away carefully. Repeat with the remaining mixture.
If you now want to grill your crumpets, transfer your pan (if it has a heatproof handle) to the grill and cook until the tops are golden brown. If your pan doesn't have a heatproof handle, transfer the crumpets to a baking sheet and grill them on that instead. Can be made up to a day ahead or frozen until ready to grill and serve.
Serving suggestionsWe've served ours with dulce de leche, butter and flaky sea salt!