Preheat the oven to 180C/350F/Gas 4.
For that relish, heat a little fry pan on the medium heat and add some essential olive oil. Fry the onion along with a pinch of salt within the oil for 4-a few minutes, or before the onion is soft. Add some garlic clove and prepare for 2 minutes, then stir within the tomato plants and also the vinegar. Lightly simmer for 5 minutes, or before the mixture has thickened to some relish consistency. Taste and adjust the seasoning as necessary. Leave to awesome.
For that onions, heat a fry pan on the medium heat and melt the butter within the pan. Add some sliced onion along with a pinch of salt. Turn lower heat and then leave the onions, stirring once in a while, to prepare for twenty five-half an hour, or until dark golden in colour and completely collapsed.
Throughout the hamburger, put the mushrooms using the stalk side facing up onto a stove tray, drizzle using the oil and season with pepper and salt. Bake within the oven for ten minutes, or until starting to soften. Meanwhile slice the mozzarella ball into four equal slices. Following the mushrooms have cooked for ten minutes, remove in the oven and put a slice of mozzarella into each one of the mushrooms on the top from the stalk. Put into the oven for five-7 minutes to melt the mozzarella.
To put together, gently toast the cut side from the hamburger buns. Spread after some relish after which put the mushrooms on the top from the bottom hamburger bun. Divide the onions one of the burgers and add any remaining relish on the top. Finish by sandwiching each hamburger using the remaining halves.
In May 2013 this recipe was costed at 3.96 at Asda, 3.37 at Tesco and three.11 at Sainsbury’s.
This recipe is made to be produced along with a