Heat a large skillet over medium-low heat and add the olive oil, then add the butter. Add the shallots and saute until translucent, a couple of minutes. Add the rice and stir to coat the rice thoroughly. Slowly add the chicken stock, about 1 cup at a time, stirring constantly after each addition. Once the rice has absorbed each addition of stock, add another cup. Continue to stir until cooked through. This process will take approximately 20 minutes. The risotto is done when it still has texture but no crunch.
Still on the heat, add the grated cheese and stir thoroughly. Fold in the chopped thyme, and then season with salt and pepper.