One of the best ways to improve performance in mentally demanding tasks is to be conscious about every single decision and the reason behind that decision, yes even for minute things like why we are craving something[1].
It introduces a non trivial amount of overhead but, with time, these processes become internalized, which improves speed while retaining the correct course of action.
I experienced this when I was climbing in competitive games. The first step was to get over the 'not my fault' mentality and transition to an 'I need to improve' mentality. I began by analyzing everything that I understood, and becoming more conscious and aware of the current situation, the available information and my mistakes and every game I was aiming to improve my play instead of winning.
[1] I remember reading that cravings are an indication of the kind of nutrients the body needs, more so than the specific food itself. When I was transitioning to a vegetarian diet, I found that I could cure/reduce my meat cravings e.g. burgers by increasing protein and fat on my next meal, my sugar cravings were associated with a) low energy or b) the need to take a break and let subconscious do the work to figure out the solution.
But all of these could be attributed to confirmation or other memory biases.