Combine the rice and 1 1/2 cups water in a small saucepan with a tight-fitting lid.
Bring to a boil, then cover and turn the heat to low.
Cook, stirring occasionally, 12-15 minutes or until the rice is cooked through. Remove from heat and set aside until serving.
While the rice is cooking, heat the oil in a large saucepan until shimmering.
Add the chicken to the pan and cook until the chicken has browned on both sides.
Add the onions and garlic to the pan and cook, stirring occasionally, until the onions have softened and the garlic has become fragrant about 3-5 minutes.
Stir in the curry powder or paste and ginger and toss to combine, then slowly whisk in the coconut milk, pumpkin puree, chicken stock, fish sauce, and lime juice.
Bring to a boil, then reduce the heat to low and simmer 10-12 minutes. Stir occasionally and let the sauce thicken slightly.
Remove the sauce from the heat, cutting up the chicken into bite-sized pieces if desired.
Serve the chicken sauce over the rice and garnish with pepitas.