In a large pot, melt the butter over medium heat. Once it foams, add the orzo and cook until golden, 2 minutes. Stir in the rice; season. Add 2 1/2 cups stock, the cranberries, scallion whites, orange zest, rosemary and bay leaf. Bring to a boil, then cover, reduce heat to low and cook until the rice is tender, 17 to 18 minutes, adding the remaining 1/2 cup stock if needed. Discard bay leaf.
Transfer the mixture to a serving dish and toss with the chopped orange, scallion greens, parsley and almonds. Season, then drizzle with EVOO.