In a large saucepan, over medium heat, add 2 tablespoons of the olive oil. When hot, add the mushrooms and saute until golden brown, about 4 minutes. Remove the mushrooms from the pan and set aside. Add the remaining tablespoon of olive oil to the same pan, and add the shallots, carrots and celery. Season with salt and pepper and saute until the vegetables start to wilt, 4 to 6 minutes. Stir in the garlic, bay leaf and thyme leaves and cook until fragrant, about 1 minute. Add the red wine and cook until almost all of the liquid is evaporated, about 3 minutes. Add the chicken stock, white beans, and reserved mushrooms; bring to a simmer and cook until sauce is slightly thickened, about 8 minutes. Remove from the heat and stir in half of the parsley. Add the butter little by little until sauce is thick and butter is completely incorporated. Taste and adjust seasoning, if necessary. Set sauce aside, keeping warm (do not allow sauce to boil or it will separate).
Season both sides of the arctic char with salt and pepper. Prepare a stovetop smoker according to manufacturer's directions using either alder or apple smoking chips. When the smoker is ready, place the char fillets on a lightly oiled tray inside the smoker and close the lid. Smoke the char over medium-high heat until just cooked through, about 20 minutes. Serve the arctic char fillets over a spoonful of the white bean and mushroom ragout. Garnish with the remaining chopped parsley and chopped chives.