In a deep flameproof casserole dish,
cook the onions in the oil for 8 mins until
soft. Add the cumin and cook for 1 min
more. Stir in the mince and add a bit more
oil, if needed. Turn up the heat and cook
for 4-6 mins, stirring occasionally, until
the mince is browned.
Stir in the chipotle paste, tomatoes
and half a can of water, and simmer for
5 mins. Mix in the beans and sweetcorn,
and cook for a few mins more until thick,
piping hot and the mince is cooked.
Heat the grill. Take the pan off the heat
and put the tortilla triangles randomly
on top. Scatter over the cheese and grill
for a few mins until the topping is crisp,
taking care that it doesn’t burn. Sprinkle
with the spring onions and serve.