Chipotle beef burgers with guacamole

• 1Red onion
• 2Limes
• 500gBeef mince
• 2 tbspChipotle paste
• 1 tspGround cumin
• 1 tbspVegetable oil
• 80gMature cheddar, sliced
• 2Avocados
• 30gFresh coriander
• 1Little gem lettuce
• 4Brioche buns
• 200gTortilla chips

Plus salt, pepper and water.

Method

1. 1

   Finely chop the onion. Put half of it in a small bowl with the juice of 1 lime and a pinch of salt, scrunch together and leave to turn pink.

2. 2

   Mix the mince with the chipotle paste, cumin, 1 tsp salt and some pepper, then shape into 4 patties about 2cm thick.

3. 3

   Heat the oil in a large frying pan over a medium-high heat and toast the cut sides of the buns for a minute. Fry the patties for 4 to 5 minutes a side, until charred and cooked through with no pink in the middle. Lay the cheese on for the last 2 minutes and cover the pan so it melts.

4. 4

   Meanwhile, mash the avocados with the rest of the onion, the juice of the second lime, most of the coriander, chopped, and a good pinch of salt. Leave it a little chunky.

5. 5

   Build each burger with lettuce, a patty, a big spoonful of guacamole, the pink onions and a few coriander leaves. Serve with the tortilla chips and the rest of the guacamole for scooping.