Throughout the cooking process I am always tasting. Concentrating on sweet, sour, salty, savory and umami. I always have room in the flavor to finish a dish with fat, acid and salt. Tasting and thinking. By building the flavor and continually tasting, the brain trains itself in portions and taste.
That is a wide variety of vegetables and in infinite amount of cooking and non cooking variables and combinations to go through. The best way to go is to constantly taste every step. For instance, I would taste a vegetable before I peeled and after.