Preheat oven to 400 degrees and grease a muffin pan with non-stick spray.
Add pecans and oats to food processor and pulse several times to grind to a coarse flour. Transfer mixture to a large mixing bowl and whisk together with buckwheat flour, baking powder, baking soda, turmeric, cardamom, ginger, cinnamon, salt, and pepper.
Add yogurt, ghee, bananas, and dates to the food processor and blend until smooth. Add this mixture along with the eggs to the dry ingredients. Fold to combine. Fold in blueberries.
Fill muffin cups half way with batter, place 1 scant tablespoon of blueberry jam in center and top with batter to fill molds.
In a small bowl, quickly combine together the ingredients for the topping and sprinkle on top of muffins.
Bake for 18 to 20 minutes. Let cool before removing from molds.