For the rice, bring the chicken stock to a boil. Add the rice, reduce heat to low, cover, and cook 18-20 minutes. Fluff rice with a fork and season will with salt. Set aside.
Heat oven to 400F.
Heat 1 tablespoon olive oil in a large nonstick skillet on high heat. Season the chicken with salt and pepper. Add the chicken to the skillet and brown on both sides (~2 minutes per side). Move the chicken to a rimmed bake sheet and put in the oven to bake until cooked through (~15 minutes). Alternatively, if your skillet can go in the oven, just put that with the chicken in the oven (I was afraid the handle on my cheap pan would melt). Once cooked, remove from the oven and set aside until cool enough to handle. Chop into bite-sized pieces.
Take the same large skillet and, using paper towels, wipe out the chicken fat. Heat the remaining 1 tablespoon olive oil on medium-high heat, and saute the onion until translucent and lightly browned. Add the butter, garlic, ginger, and spices. Cook briefly (~30 seconds).
Reduce the heat to low and add the chicken, tomatoes, evaporated milk, and yogurt. Simmer gently 15 minutes to blend flavors and thicken a bit.
To finish, add the cashews and lemon juice. Both are important for the flavor of this dish, but the cashews also act as a thickening agent. Serve over the basmati rice with naan bread and garnish with fresh parsley. Serves 4.