1/2 cup coconut oil, butter or ghee, melted plus more for the griddle or skillet
Place the rice in a sieve and rinse well. Place rice in a medium saucepan and add 2-1/4 cups water. Bring to a boil, reduce heat, and simmer uncovered for 1 hour. Grains should be puffed and open. If not, remove the saucepan from heat and let rice stand in the hot water until puffed, then drain thoroughly. Check the rice while it’s cooking as the water may need to be replenished.
Sift the flour with baking powder, salt and pepper, and ground vanilla bean powder, in a large bowl. Add walnuts. Beat eggs with a fork. Add sour cream (or yogurt) and 1/2 cup milk. Mix well and then add the rest of the milk and butter (or oil). Mix into the flour mixture. Add in vanilla extract if using, then fold in the cooked rice.
Spoon batter into a slightly buttered cast-iron griddle or skillet that is hot but not smoking. Cook until bottoms are golden brown and pancakes begin to set, about 3 minutes. Turn and cook on the other side for 1 minute or until lightly browned. Keep pancakes warm on an ovenproof platter until all pancakes are cooked.