Eat. Real. Food.
Limit the processed stuff as much as possible, but especially off the bike.
During rides smash all the simple sugar snacks you want. Whatever your body tolerates well. Sometimes sugar is sugar and off the shelf candy can give expensive “performance products” a run for their money. Just read labels and look for glucose as a sugar source. Haribo Gold bears…
Off the bike I don’t count calories or macros but try to get my carbs from things like veggies, sweet potatoes, and short grain brown rice. I eat a fair bit of meat for protein and lots of eggs. Eggs and spinach with rice plus some soy sauce and sriracha is a staple. Leafy greens and a vegetable with every meal is a good rule if thumb. Snacks are almonds, fruit and a lot of whole grain toast with peanut butter honey and bananas. Clif bars and such as well if I’m commuting or traveling and desperate.
FasCat has a good podcast on nutrition that they call winning in the kitchen that’s worth a listen. Very even handed and not overly scientific approach which I appreciate.
Post workout I may supplement some protein but try to get most of my needs covered with food, not supps.
If you want to drill down, I have used the my fitness pal app in the past and it’s a great tool for measuring what you’re eating. If you try it for a week you can get a baseline and the result may surprise you. I was running deficits everyday and had no idea. Good for weight loss, bad for training.