Equipment
Ingredients
Potato Base
- 1 baking potato, scrubbed clean
- 10 g unsalted butter, room temperature
- flaky sea salt
Beans and Cheese Filling
- 100 g baked beans in tomato sauce
- 30 g cheddar cheese, grated
Tuna Sweetcorn Filling
- 60 g canned tuna in spring water, drained well
- 30 g sweetcorn kernels, canned or thawed from frozen
- 30 g mayonnaise
- black pepper, freshly ground
Nutrition (per serving)
Nutrition is estimated per serving. Nutrients without complete source data are omitted.
Full nutrition
- Calories
- 724 kcal
- Protein
- 32 g
- Carbohydrates
- 60 g
- Fat
- 42 g
- Fiber
- 12 g
- Sugar
- 10 g
- Sodium
- 1738 mg
- Saturated Fat
- 15 g
- Trans Fat
- 0 g
- Monounsaturated Fat
- 8 g
- Polyunsaturated Fat
- 14 g
- Cholesterol
- 56 mg
- Potassium
- 1548 mg
- Calcium
- 350 mg
- Iron
- 11.4 mg
- Magnesium
- 118 mg
- Phosphorus
- 431 mg
- Zinc
- 4.9 mg
- Vitamin A
- 169 mcg
- Vitamin C
- 32 mg
- Vitamin D
- 0.8 mcg
- Vitamin E
- 1.6 mg
- Vitamin K
- 51 mcg
- Vitamin B6
- 0.9 mg
- Vitamin B12
- 1.6 mcg
- Thiamin
- 0.19 mg
- Riboflavin
- 0.24 mg
- Niacin
- 9.6 mg
- Folate
- 75 mcg
- Water
- 381 g
Sources: Aggregated Public Data, USDA FoodData Central
Method
Scrub the potato under cold water and pat completely dry. Prick the potato deeply all over with a fork about 8 to 10 times to allow steam to escape during cooking.
Place the potato on a microwave-safe plate. Microwave on full power (800W to 1000W) for 5 minutes.
Using an oven mitt, carefully flip the potato over. Microwave on full power for an additional 4 to 5 minutes.
Remove the plate from the microwave. Allow the potato to rest for 2 minutes to finish steaming internally.
While the potato rests, combine the drained tuna, sweetcorn, mayonnaise, and black pepper in a small bowl. Mix thoroughly.
Pour the baked beans into a small microwave-safe dish. Heat in the microwave for 1 minute, or until they reach 74C/165F and are bubbling slightly.
Slice a cross into the top of the resting potato, cutting about halfway through. Pinch the base of the potato inward to push the fluffy flesh upward and open the cuts. Add the butter and a pinch of flaky sea salt to the flesh.
Spoon the hot baked beans onto one half of the potato, topping immediately with the grated cheddar cheese so it melts. Spoon the cold tuna sweetcorn mixture onto the other half. Serve immediately.
Chef's Notes
- Resting the potato for two minutes after microwaving is crucial; it allows carryover cooking to gently soften the very core without overcooking and drying out the outer layers.
- If you have an extra 10 to 15 minutes, you can achieve an oven-baked texture by microwaving the potato for 8 minutes, rubbing the skin lightly with oil and salt, and finishing it in an oven at 200C/400F.
- Ensure your canned tuna is thoroughly drained before mixing with the mayonnaise, otherwise the filling will become watery and seep into the potato flesh, making it soggy.
Storage
Refrigerator: 2 days — Store toppings and potato in separate airtight containers.
Troubleshooting
Potato is still hard in the center after full cooking time
Cause: Potatoes vary significantly in size and density, or the microwave has a lower wattage
Fix: Return the potato to the microwave in 1-minute bursts on high until a knife pierces the center easily
Prevention: Weigh potatoes to ensure consistency and learn how your specific microwave performs
Potato bursts or explodes in the microwave
Cause: Trapped steam built up pressure under the unbroken skin
Fix: Cannot be fixed
Prevention: Pierce the potato deeply and thoroughly all over with a fork prior to cooking
Skin is soft and slightly wrinkled rather than crisp
Cause: Microwaves heat via internal moisture, effectively steaming the skin rather than drying it out
Fix: Transfer the microwaved potato to a preheated 200C/400F oven for 10 minutes to dry out the skin
Prevention: This is inherent to microwave cooking. For crisp skin, oven baking is required
Cultural Context
The jacket potato is an iconic British comfort food and pub classic, traditionally baked slowly in special cast-iron ovens until the skin is thick, crisp, and slightly charred. Adapting it for the microwave makes this filling, highly versatile dish accessible for quick weekday lunches while still supporting heavy, savory toppings like the classic split of baked beans with cheese alongside tuna mayonnaise.
