Meat. It's really that simple. Meat is the most efficient source of nutrient dense food that won't wreak havoc on our sugar metabolism. I fought the obvious for years and insisted on following the Conventional Wisdom for a healthy varied diet. But it turns out my carnivore friends had a point about the benefits they claimed for their diets. Although I'm no purist and don't do full keto.
Cook up a bunch of chicken fingers seasoned to your liking, enough to last a few days of snacking.
Cut back on the carbs and sugar. I still eat that stuff, but I try to limit it to fuel for workouts and harder bike rides. Although I ate some pecan pie today, on a rest day. I didn't explode.
I cut out beer and alcohol completely this year. Couldn't seem to metabolism alcohol anymore after my thyroid failed, and ended up with hangover symptoms after a single beer. Kinda took all the pleasure out of beer. I lost 10 lbs of belly fat. I was surprised to discover how much of my calorie intake was beer, especially those tasty and strong local craft beers. (Saved a lot of money too, for bike stuff or... food.)