From www.greenkitchenstories.com

These muffins are a hit in my house. They make a healthy and satisfying breakfast on the go. They can easily be made vegan by substituting 3 tbsp of chia seeds mixed with 9 tbsp water for the eggs, and replacing the buttermilk with a vegan yogurt.

Dry ingredients
100 g / 1 cup walnuts
85 g /1 cup rolled oats
90 g / 2/3 cup buckwheat flour + 2 tbsp arrowroot 
1 1/2 tsp baking powder
1/2 tsp baking soda
1 tbsp turmeric (I used less for my kids)
1 tsp freshly ground cardamom
½ tsp sea salt
a pinch black pepper

Wet ingredients
160 ml / 2/3 cup buttermilk or yogurt
80 ml / 1/3 cup olive oil or butter
2 ripe bananas, mashed
5 fresh dates, mashed
3 large eggs 

A large handful blueberries, frozen or fresh

Granola topping
1/3 cup rolled oats
2 tbsp olive oil/coconut oil
1 tbsp honey

Preheat the oven to 400°F. Line a muffin pan with paper liners or grease the pan. Add walnuts and rolled oats to a food processor or blender and mix quickly into a coarse flour. Transfer to a large mixing bowl together with the rest of the dry ingredients. Add buttermilk, oil, bananas and dates to the food processor or blender and mix until smooth, then transfer to the mixing bowl with the dry ingredients. Crack the eggs in a separate bowl and beat them for about a minute before adding. Use a spatula to carefully fold everything until combined. Divide the batter into the muffin tins, drop a bunch of blueberries on top of each muffin and gently push them down a bit. Mix together the granola crumble in a small bowl and add it on top of the muffins. Bake for about 18-20 minutes. Best enjoyed still warm from the oven.