Pre-heat your oven to gas mark 4/180c.
In a saucepan, add 1 tablespoon olive oil and being it up to a medium heat.
1 tablespoon olive oil
Fry the onion until soft.
2 red onions
Add the garlic and mushrooms, stir frequently.
3 cloves garlic, 350 g portobello mushrooms
After 5 minutes, stir in the purée, marmite and nutritional yeast flakes.
6 tablespoon tomato purée, 2 teaspoon marmite, 4 tablespoon nutritional yeast
Season with salt and pepper.
Stir in the breadcrumbs until everything is mixed.
200 g breadcrumbs
Grease a small loaf tin or mould.
Pop the mix in the loaf tin and spread evenly.
Put in the oven for 40 minutes.
Leave to cool for 5 minutes before removing from the tin and slicing.