Place onion, garlic, chilli and EVOO into the Thermomix bowl. Chop 3 sec/speed 6. Saute 5 min/Varoma/speed 1.
Add dry spices and cook 2 min/Varoma/speed 1.
Insert Butterfly. Add salt, pepper, sugar, mushrooms and tomatoes. Cook 30 min/Varoma/speed soft.
Assemble tacos adding salsa, feta, avocado, spring onions to taste.