Preheat the oven to 350F. Line a muffin tin with liners and set aside. 

To make the streusel: In a small saucepan, set over medium heat, add the coffee grounds and butter. When the butter has melted, allow the coffee to steep in the butter for about 3 minutes. Run through a very fine mesh strainer, discarding the grounds, and adding the coffee-butter to a small bowl. Add the sugars, spices and flour. Mix with your hands until clumpy. Set aside. 

To make the muffins: In a medium bowl, whisk together the all-purpose flour, whole wheat or spelt flour, ground cinnamon, baking soda, baking powder and salt. In the bowl of a stand-up mixer, with the paddle attachment, add the butter and sugars; beat until light and fluffy, about 3 minutes. Add the eggs and beat until incorporated. Next, add the yogurt or sour cream and vanilla. Add the dry ingredients, in two batches, until barely combined. Lastly, fold in the diced pear. Divide the batter amongst the 12 muffin cups, filling them about 3/4 of the way.  Top each muffin with a handful of the streusel topping. Transfer to the oven to bake for about 17 to 20 minutes, until a skewer comes out clean when inserted into the center.