1 tbsp chopped coriander, plus extra leaves to serve
Four small soft corn and flour tortillas
75g feta, crumbled (optional)
4 tsp hot sauce, or to taste
Finely slice the pale green parts of the spring onions and set them aside.
Finely chop the white parts of the spring onions and put them in a frying pan with the olive oil.
Set the pan over low heat and cook the onions for 2 mins.
Add the cumin and a pinch of salt and continue to cook for 2 mins.
Stir in the drained black beans, heat through for a minute or two, then remove from the heat, season well and crush the beans with the back of a wooden spoon to make a mash.
Using a fork, mash the avocado flesh with the juice of half a lime, half the sliced chili, and the chopped coriander. Season well.
To poach the eggs, fill a deep frying pan with water at least 5cm deep.
Bring to a boil, then reduce the heat to a gentle simmer. Crack the eggs into the water, leaving sufficient space between each, and go to poach for 4 mins until the whites are set, but the yolks are still runny in the center.
Remove with a slotted spoon and drain on a kitchen towel.
Rinse and dry the frying pan and return to medium heat.
Toast the tortillas for 1 min each side, in batches if necessary, or until crisp.
Spread each tortilla with the black bean mixture, followed by a spoonful of crushed avocado.
Top with a poached egg and a scattering of sliced spring onion, sliced chili, extra coriander leaves, crumbled feta (if using), and hot sauce to taste.
Slice the remaining half lime into four wedges to serve.