In a large saucepan over medium heat soften the onion and garlic in the olive oil, about 5 to 6 minutes. Add the chicken stock and increase heat to high. Bring to a boil.
Constantly whisking, slowly add the cornmeal (about 2 tablespoons at a time) to the stock. Cover the polenta and place in the oven. Cook for 45 minutes, stirring every 15 minutes to prevent burning and clumping.
Remove the polenta from the oven. Add the butter and stir well to incorporate. Add the gruyere, mascarpone and salt. Stir well.
Plate the polenta and top with sautéed chard, mushrooms and a light drizzle of smoked paprika-garlic butter.