Potato Bean Pie.

A back-to-basics vegetarian main that uses what’s already in the pantry. Canned kidney beans, tomatoes, mushrooms, and a layer of fluffy mashed potatoes come together in a pie pan and bake into something halfway between cottage pie and Irish shepherd’s pie.

The beauty is in the flexibility. “To taste” on the tomatoes and mushrooms means you adjust based on what’s on hand. Canned tomatoes work well, but fresh tomatoes chopped coarsely and tossed in give a brighter, more summery flavor.

Pre-seasoning the components matters. This recipe skips explicit seasoning details, which means salt, pepper, garlic, and herbs are entirely up to the cook. A sprinkle of salt, a grind of pepper, and a pinch of dried thyme or oregano stirred through the beans and vegetables transforms a bland bake into a flavorful one.

The 40-minute bake is where the potato crust sets into a golden, craggy topping. Dragging the tines of a fork across the mashed potatoes before they go in creates ridges that crisp up beautifully in the oven.

Kitchen Tips

• Drain and rinse the kidney beans thoroughly. Canned bean liquid is salty and can make the filling too wet.
• Sauté the mushrooms first to release their water. Raw mushrooms leach too much liquid during baking and can make the filling soupy.
• Warm the mashed potatoes before spreading. Cold potato is difficult to spread evenly over the filling.

Variations

• Add a layer of sautéed spinach between the beans and the potato crust for extra greens.
• Top the potato layer with grated cheddar in the last 10 minutes for a cheesy crust.
• Swap kidney beans for black beans or chickpeas for a different bean profile.