Pickle the onions • Peel and finely slice the red onion and add to a bowl • Add the vinegar, salt and sugar and toss to combine, squeezing them firmly with your fingers • Set aside
Cook the potatoes • Chop the potatoes into 1–2cm chunks and put them into the microwaveable bowl • Cover with clingfilm and microwave for 5 minutes until soft
Meanwhile, cook the mushrooms and sausages • Slice the mushrooms and roughly chop the sausages • Put the large frying pan over a high heat and add the oil • Add the sausages to the hot oil and stir roughly to break them up • Add the mushrooms and pinch of salt • Fry for 5 minutes, stirring occasionally
Make the tacos • Put the medium frying pan over a high heat • When the pan is hot, drop in a tortilla and toast for about 15 seconds • Flip and toast for another 15 seconds • Transfer to a plate and cover with a tea towel • Repeat with the remaining tortillas
Prep the veg • Halve and stone the avocado, peel and slice the flesh, place in a bowl and set aside • Cut the lime into wedges • Quarter the cherry tomatoes • Slice the spring onions
Finish the hash • Take the potatoes out of the microwave and toss them into the sausage pan • Peel the garlic then grate it directly into the pan • Sprinkle over the fajita seasoning • Cook for 2 minutes • Add the fresh spinach and cook until wilted • Add the chopped cherry tomatoes and half the spring onions • Season to taste • Remove from the heat
Serve • Shape the tortillas into pockets in your hands and fill them with hash • Top with picked onions, sliced avocado, hot sauce, if using, fresh coriander and the remaining spring onions. Or bring everything to the table and let everyone build their own!