Generously sprinkle the steaks with salt and fresh ground black pepper 1 hour before cooking and hold in the refrigerator.
Heat the butter and olive oil in a large saute pan over medium heat. Add the leeks and saute until soft, 3 minutes. Add the garlic and saute for another 2 minutes. Reduce the heat, add the chicken broth and season with salt and pepper. Continue to cook until the leeks are tender and the liquid is mostly absorbed, 6 to 8 minutes. Stir in the heavy cream and continue to cook for 3 to 4 minutes.
Preheat the oven to 325 degrees F.
Heat 2 heavy-bottomed or cast-iron skillets over high heat. Add 3 tablespoons of the canola oil to each skillet. Place a steak in each pan and sear 2 to 3 minutes per side. Transfer the skillets to the oven and cook until an internal thermometer inserted into the steaks reads 130 degrees F, 6 to 8 minutes. Rest the meat for 10 minutes. Slice the steaks and serve with the leek sauce.