It's not something i'd ever tried before last month either, as i am actually not a fan of lentils or beans 
Here you go:
Vegan Chilli (made six portions)
1 can kidney beans, rinsed and drained
1 1/2 chopped tomatoes or passata
3 cloves garlic, crushed
3 fresh chillies, deseeded and chopped
3 small onions, chopped
1 courgette, cut into rounds and then quartered (any veg will do)
2 peppers (any colour), diced (i like carrots instead)
100g frozen sweetcorn
1/2 bag spinach (or some frozen spinach)
1 tsp mixed spice
1 tbsp chilli powder
1 tsp ground cumin
25g red lentils
1 tbsp dried oregano
juice of 1 lime
a few dashes of soy sauce
Heat a little vegetable oil in a large, deep-sided frying pan and gently fry the onion, peppers and chilli for a few minutes until soft.
Add the courgette (or carrots/peppers/whatever veg you choose to use), continue to cook, and add the garlic for the last minute.
Add the chopped tomatoes, spices and red lentils. Cook for 45 minutes to an hour, adding extra water as the lentils absorb it and stirring occasionally.
Ten minutes before the end of cooking, pop the spinach in a sieve and pour hot water over it to wilt, then add, along with the sweetcorn and kidney beans, to the pan to finish cooking. Right at the end, once the lentils are cooked and vegetables tender, add in the lime juice and soy sauce and season to taste.
It is really lovely!