Stir in the crushed tomatoes, sweetcorn, black beans and chicken stock. Bring the stew to a gentle boil, then lower the heat and let it simmer, covered, for 20 minutes, stirring occasionally.
2 cans (14 oz / 400 g) crushed tomatoes
1 can (7 oz / 200g) sweetcorn
1 can (14 oz / 400 g) black beans
2 cups chicken stock