Add the first 7 ingredients to a bowl and mix well. Beat the egg and combine with the mixture.

Divide the mixture into 4 burger sized portions (or 8 smaller portions if preferred) and bake in a 375°F oven for 25-30 minutes until the burgers start browning on the top. Optional: 5 minutes before the end, add a pinch of grated cheese to each burger so that it melts over the top.

While the burgers are cooking, make the tomato sauce: heat the tomatoes in a pan, then add the garlic, Dijon mustard, chilli powder and tomato puree. Bring to a boil, then reduce heat. Add the spinach and cook until wilted. Let cool slightly, then coarsely blend using an immersion blender. Season with salt and pepper to taste.

To serve, divide the tomato and spinach sauce into 4 individual bowls and a place a cauliflower cheese burger on top. Enjoy!