The key to prepping a full week of food in 2 hours is parallelisation - running multiple cooking processes simultaneously. While your oven roasts vegetables, your stovetop cooks protein, and your rice cooker handles grains. Maximising your kitchen multitasking is what separates a 2-hour prep session from a 4-hour ordeal.
Start with what takes longest in the oven (typically 30-40 minutes): pre-cut vegetables (broccoli, sweet potato, capsicum), chicken thighs or salmon fillets seasoned and ready to roast. While the oven runs, start your rice or quinoa in a pot or rice cooker (20-25 minutes). Simultaneously, cook your ground beef or chicken breast in a pan on the stovetop (10-15 minutes). By the time the oven finishes, everything else is done.
While food cools (10-15 minutes - never container hot food as it raises refrigerator temperature), hard boil a batch of eggs (12 minutes, can run during cool-down). Then portion and container everything. For 5 days of lunches and dinners, you'll need approximately: 1.5-2kg of protein, 2-3 cups of dry grains, and 3-4 types of vegetables. Keep sauces and dressings separate to maintain food texture and keep meals interesting throughout the week. Label containers with the day or meal to remove any decision-making during the week.