- Preheat the oven to 350 degrees F. Line 12 muffin tins with paper liners or spray the pan with a non-stick spray. 
- In a small saucepan, bring the buttermilk to a gentle simmer over medium to low heat. Remove from heat. Add the tea bags and steep for about 20 minutes. Discard the tea bags. 
- For the streusel, add the flour, brown sugar, cinnamon, and butter to a small bowl. Mix together with your hands until you have a crumbly mixture. Alternatively, you may place the ingredients in a food processor and pulse 4-5 times or until the mixture is crumbly/sandy. Set aside. 
- Whisk together the butter, maple syrup, vanilla, steeped buttermilk, greek yogurt, and eggs in a large mixing bowl until smooth. Add the flour, baking powder, baking soda, cinnamon, and salt. Fold the ingredients together until just combined. Do not over-mix. Gently fold in the blueberries and blueberry jam, being careful not to over mix.
 
 
- Divide the batter among the prepared tins. Evenly sprinkle the streusel over the batter. Transfer to the oven bake for 30 minutes or until a toothpick comes out clean. Serve with a pat of butter.