Some tender veggies like cauliflower breaks away in the cooking pan as soon as it softens . To get the right colour and texture of the finished recipe for such ingredients, cook at highest heat level for first 5-10 minutes. Make sure to keep turning the ingredients occasionally so that some pieces get brown even though not tender or cooked fully. After you get the right colour and burnt flavour, alternate the heat to low to let the ingredients get tender and fully cooked. You may want to add a few drops of water when putting the heat at low to help tendering process and finish up the recipe.