Soak the kidney beans in 1% salted water for about 6-8 hours. As the first step, before preparing ingredients, drain the soaked beans, add to a large sauce pot and cover with plenty of water. Cover and turn heat to high. While it comes to a boil, put your various bean spices (kombu, bay leaf, etc.) into a disposable or reusable spice bag and add to the water. Boil for at least 10 minutes, for kidney-bean-safety reasons. Then turn down heat to a gentle simmer and cook for another 15-45 minutes, checking frequently, until softened 99% of the way. (They will cook very slightly more in the oven.)
300 g dry kidney beans, Kombu, bay leaf, other bean spices
Prepare all ingredients as above and measure out spices as needed. Then, quarter the onion. Thinly slice half and set aside. Rough chop the remaining half and add to a small food processor with the garlic, serrano and ginger. Chop until small, scraping down the sides as needed.
1 large red onion, 4 cloves garlic, 1 serrano pepper, 1 inch fresh ginger
When beans are nearly done, begin the next steps. In a large, oven-proof skillet, preferably with high walls, heat 2 tbsp oil over medium. Add the cumin and mix for 30 seconds. Then add the ginger, onion and pepper mix and cook until the excess liquid has evaporated and the mixture is just starting to darken (8-10 minutes).
2½ tbsp neutral oil, 1 tsp cumin, 1 tsp salt
Preheat the oven to 350ºF with a sheet pan on one shelf. Mix the cubed paneer with about ½ tbsp oil, just enough to cover, and a light dusting of salt and pepper.
14 oz paneer
Add the cooked, drained beans and the ancho chile powder to pan and mix. You can mash a small portion of the beans (1-2 tbsp worth) to help thicken the sauce, if you'd like. Add the crushed tomatoes, garam masala and fenugreek leaves to the pan. Stir well and allow to cook for 1-2 minutes on the stovetop.
28 oz canned crushed tomatoes, ½ tsp ground ancho chile powder, ¼ tsp garam masala, ½ tsp fenugreek leaves
Spread the paneer onto a sheet pan. Place the paneer in the oven and set a timer for 7 minutes (for flipping the cheese). Cook the paneer until golden on a few sides, maybe 15-20 minutes. When done, add directly to the beans/sauce and mix before allowing to cook longer.
At the same time as the paneer, add the rajma pan, uncovered, to the oven and cook for 30 to 40 minutes total, until the sauce has thickened. Stir 1-2 times while cooking, including when you add the paneer about halfway through. (See prior step.)
While everything bakes, pickle the thinly sliced onion. Boil water in the kettle. Add the sliced onions to a bowl. Pour boiling water on top and allow to sit for 30 seconds. Drain. In the wiped-clean bowl, stir together the rice wine vinegar, sugar and salt until dissolved. Add the reserved onion slices to the bowl and stir in the vinegar. Allow to marinate.
1 tsp granulated sugar, ¼ cup rice wine vinegar, 1 tsp kosher salt
When the beans and paneer is done, garnish with the pickled onion slices, letting a few drops of the pickling liquid flick over the beans to season them. Garnish with cilantro and serve with rice or naan.
½ bunch cilantro