High-Fiber Meal Prep: Cook Once, Eat Well All Week

Legumes and whole grains - the foundation of a high-fiber diet - are also the most batch-cook-friendly foods in the kitchen. A cup of dried lentils costs under a pound, cooks in 20 minutes, and produces enough for four meals. Cooked grains last 5 days in the fridge. Bean soups freeze for three months. The economics of high-fiber meal prep are genuinely good.

The plan below takes about 90 minutes of active cooking on Sunday and produces five days of lunches and dinners averaging 25-30g of fiber per day from those two meals alone.

What to Cook on Sunday

1. Big Pot of Lentil Soup (45 minutes, makes 6 portions)

Sauté 2 diced onions, 3 cloves garlic, 2 diced carrots, and 2 stalks of celery in 2 tablespoons of olive oil until soft. Add 400g dried green lentils (rinsed), 2 tins of chopped tomatoes, 1.5 litres of vegetable stock, a tablespoon of cumin, a teaspoon of smoked paprika, and salt and pepper. Bring to a boil, reduce to a simmer, cook 25-30 minutes until lentils are completely tender. Adjust seasoning and add a squeeze of lemon before serving.

Storage: refrigerate up to 5 days, freeze up to 3 months. Reheats in 3-4 minutes. Per serving: ~350 kcal, ~16g fiber, ~18g protein.

2. Grain Base: Farro or Barley (25 minutes, makes 4-5 cups cooked)

Cook 1.5 cups of dried farro or pearled barley in lightly salted water according to package instructions (typically 25-30 minutes for farro, 30-35 for barley). Drain, season with a tablespoon of olive oil and salt. Store in a container in the fridge.

Storage: refrigerates for 5 days. Per cup cooked: ~215 kcal, ~4-6g fiber. Use as a base for grain bowls, stir through soups, or serve alongside any protein.

3. Roasted Chickpeas (30 minutes, makes 4-5 portions)

Drain and thoroughly dry 2 tins of chickpeas (wet chickpeas steam rather than roast). Toss with 2 tablespoons of olive oil, a teaspoon of smoked paprika, a teaspoon of garlic powder, and a generous pinch of salt. Spread on two baking trays - single layer, no crowding. Roast at 200C/400F for 25-30 minutes, shaking the trays halfway, until golden and crispy.

Storage: airtight container at room temperature for 2-3 days (they soften in the fridge). Per half-cup: ~160 kcal, ~6g fiber, ~8g protein.

4. Black Bean and Sweet Potato Chilli (40 minutes, makes 6 portions)

Sauté onion and garlic, add 2 diced sweet potatoes, 2 tins of black beans, a tin of chopped tomatoes, 200ml vegetable stock, cumin, chilli powder, and a square of dark chocolate (optional - it adds depth). Simmer 25-30 minutes. Per serving: ~400 kcal, ~16g fiber, ~13g protein.

Storage: refrigerates 5 days, freezes 3 months. Serve over a scoop of the cooked grain base.

5-Day Meal Plan Using Sunday's Prep

Monday

Lunch: Lentil soup (1 portion) + 2 slices of whole-grain bread. ~590 kcal, ~20g fiber.
Dinner: Black bean chilli over farro with sliced avocado. ~640 kcal, ~22g fiber.

Tuesday

Lunch: Farro bowl with roasted chickpeas, cucumber, cherry tomatoes, and lemon-tahini dressing. ~480 kcal, ~14g fiber.
Dinner: Lentil soup (1 portion) + a side of roasted broccoli. ~480 kcal, ~19g fiber.

Wednesday

Lunch: Black bean chilli over farro (lunch portion). ~500 kcal, ~18g fiber.
Dinner: Farro bowl with roasted chickpeas, wilted spinach, and a poached egg. ~520 kcal, ~13g fiber.

Thursday

Lunch: Lentil soup (1 portion) + 6 whole-grain crackers. ~480 kcal, ~18g fiber.
Dinner: Black bean chilli (last fridge portion) with brown rice. ~580 kcal, ~18g fiber.

Friday

Lunch: Last lentil soup portion + side salad. ~430 kcal, ~17g fiber.
Dinner: New cook - or defrost a frozen portion of chilli from Sunday's batch. ~400 kcal, ~16g fiber.

Storage Summary

• Lentil soup: fridge 5 days / freezer 3 months
• Black bean chilli: fridge 5 days / freezer 3 months
• Cooked grains: fridge 5 days (do not freeze - texture degrades)
• Roasted chickpeas: room temperature 2-3 days

Meal Prep Tips

The only active crossover needed during the week is adding fresh toppings (avocado, cucumber, tomatoes) and boiling an egg or two - everything else is reheat-and-assemble. For the broader context of how this prep fits into a full high-fiber eating plan including breakfasts and snacks, see our complete guide to high-fiber meal planning.