Add the spinach, stir well and season with salt and black pepper. To serve, place the mushroom mixture onto a serving plate and top with the tofu. Garnish with the sliced chilli.
Drain on a plate lined with kitchen paper. While the tofu is frying, make the sauce. Put the maple syrup, ketchup, vinegar, sugar and chilli flakes in a small saucepan over a medium heat.