In a medium pot over medium to medium-high heat, add EVOO and butter. Once the butter melts, add the onion, salt and freshly ground black pepper. Cook, stirring frequently, for 2 minutes.
Add rice and stir to coat in the butter and oil, toasting rice for 1-2 minutes. Add the stock and bring up to a bubble, then turn heat down to medium and cover the pot. Cook for about 18 minutes, until the rice is tender. Add the sliced almonds and fluff with a fork.