Gather and prepare your ingredients.
Heat half the olive oil in a frying pan over medium-high heat. Add the onion, garlic and a light sprinkle of salt and pepper. Cook for 3-4 minutes until softened and translucent.
Add the mushrooms to the pan and sprinkle lightly with salt and pepper. Cook, stirring occasionally, for 3-4 minutes, until reduced. Then add the tempeh, paprika, tomato puree and tamari and cook, stirring often, for a further 5-6 minutes, until everything is darkened, sticky and caramelised. Remove from the heat, stir through the oats and allow to cool slightly.
Place the mixture into a food processor and mix until you have a coarse paste. It should hold together when you squeeze it and have some larger chunks remaining.
Shape into 4 equal sized balls and then flatten into patties, about 10cm in diameter and 1.5cm thick.
To cook, heat the remaining oil in a frying pan over medium-high heat. Add the patties and cook for 4-5 minutes on each side, until nicely coloured all over the surface.If you are using cheese add it now, turn down heat to low, cover and allow to melt, 1-2 minutes.
Serve in burger buns, if desired, with your favourite toppings with your favourite toppings of ketchup, mayo, mustard, etc.