Mirepoix kimchi and vegetarian umami chilli: Kenji Morimoto’s recipes for cooking with homemade ferments

Cooking with ferments brings a tremendous amount of flavour to whatever you’re making, and it’s a great way to showcase how an ingredient evolves through the application of heat. The idea of combining a Korean preservation method with a French technique is exactly what I love about creativity in the kitchen. This mirepoix kimchi is not just a fun ferment to dot on savoury oatmeal or eat alongside cheese, but it also acts as the backbone for a plant-based, umami-filled chilli. Mirepoix kimchi (pictured top) This versatile, umami-rich paste is a twist on the classic mirepoix and can be used to add a hit of flavour to everything from soups to marinades, or even enjoyed as is. Prep 10 minFerment 2 weeks+Makes 500ml jar 150g carrot150g white onion150g celery13½g salt (or 3% of the total weight of the first three ingredients)½ tbsp red miso, or fish sauce½ tbsp sugar15g gochugaru chilli flakes Roughly chop the vegetables (there is no need to peel the carrots if they have been rinsed), then put them in a food processor. Add the remaining ingredients and blitz to a rough paste. Decant the paste into a sterilised 500ml jar and pack it down to ensure there are no air pockets; there may not be much brine, so to minimise oxygen exposure, lay a piece of greaseproof paper on top of the mirepoix to act as a barrier. Seal the jar and leave to ferment at room temperature and out of direct sunlight for at least two weeks. At the two-week mark, start tasting the kimchi and, once you’re happy with the flavour and tang, store the jar in the fridge. Vegetarian umami chilli This plant-based chilli is a powerhouse of flavour, thanks to the mirepoix kimchi and miso offering layers of heat and umami. It can easily be bulked out with your favourite chilli toppings and accompaniments, such as a jacket potato or rice. Prep 20 minCook 3 hr+Serves 4-6, with leftovers 1 tbsp olive oil250g mirepoix kimchi (see recipe above)50g tomato paste2 400g tins chopped tomatoes2 400g tins red or kidney beans, drained100g dried red lentils, rinsed400ml water2 mild chillies, stalks, pith and seeds discarded, flesh chopped3 tbsp red miso25g dark chocolate1 tsp smoked paprika2 tsp chipotle chilli flakes2 tsp oregano2 tsp ground cumin1 tbsp ground coriander To garnishChopped fresh corianderLime wedgesSoured cream, or creme fraiche or greek yoghurtGrated cheddar Put the oil in a pan on a medium-low heat, then add the mirepoix kimchi and the tomato paste, and cook, stirring, for three to five minutes, until the residual liquid from the kimchi has evaporated and the paste turns dark and aromatic. Transfer the kimchi mix to a slow cooker, add all the other ingredients other than the garnishes, and cook on low for six hours, or on high for two to three hours. Season to taste with salt, but bear in mind that there is a fair bit of salt already from both the kimchi and the miso. Serve with your favourite chilli toppings, such as fresh coriander, lime wedges, soured cream (plant-based, if need be) or cheddar. Ferment: Simple Ferments and Pickles, and How to Eat Them, by Kenji Morimoto, is published by Pan Macmillan at £22. To order a copy for £19.80, visit the guardianbookshop.com