My hack is to buy ingredients, not meals.
Meat, fish, fruits, vegetables, oil, vinegar, eggs, oats, flour, butter, plain yogurt, honey, nuts, spices. This is mainly what I buy. Very little processed food.
Ok, I do buy bread (gf). Of course, I have a shelf in the fridge full of condiments, and I always have maple sugar for my homemade gf pancakes. But for things like salad dressing, I just make it (oil and vinegar plus whatever else you can dream up).
If I want a treat, I'll bake something from scratch.
If I want a snack, I'll make low sugar granola.
Or roast some almonds.
Stay away from highly processed food, you'll save money and be healthier.