Stir the flour, baking powder, egg, milk and black pepper to a thick paste. Add the squash and sweetcorn, stir well and set aside for 5 minutes.
Meanwhile heat the oil in a large frying pan on a low heat. Transfer a heaped tablespoon of the mixture into the pan, then repeat until you have four spoonfuls gently frying, well-spaced.
After 2 - 3 minutes use a slice to flip and fry each fritter on the other side for 2 - 3 more minutes. (You can squash the fritters gently to speed the process up at this point.) Remove from the pan and drain on kitchen roll, then repeat with the rest of the mixture. Serve warm as finger food with or without dips.
Note: These keep in the fridge for 3 days, well wrapped. Re-heat in a preheated oven at 180C/gas mark 4 for 5 minutes before serving.