There is no cheaper hot meal in Britain than dahl. A bag of red lentils, a few vegetables past their prime, some spices and water — that is genuinely the whole recipe. This cheap lentil dahl batch cook makes 8 generous portions for around £6.40 total, which works out at 80p a portion, and it might be the most forgiving recipe you will ever learn. Dahl is the backbone of every serious budget meal prep routine for good reason: it costs almost nothing, it is naturally filling thanks to all that fibre and plant protein, it freezes perfectly, and it reheats better than almost anything else. Make it once and…