Preheat oven to 375 degrees and place muffin papers in a 12-cavity muffin tin.
In a large bowl, whisk together flour, baking powder, baking soda, cinnamon, ginger, and salt.
In the bowl of a stand mixer or in a large bowl with a hand mixer, cream together butter and both sugars until light and fluffy, 2-3 minutes.
Add eggs one at a time beating after each addition. Add vanilla and mix to combine.
Add half the milk and ½ the dry ingredients and mix until just combined. Add remaining milk and remaining dry ingredients and mix again until just combined, taking care not to over-mix.
Fold the diced pear into the batter.
Fill muffin papers about ¾ of the way with batter. Equally disperse crumb topping over the tops of the batter.
Bake muffins for about 20 minutes, until a toothpick inserted into the center comes out clean. Let muffins cool in tin for a few minutes before moving to a metal rack to cool completely.
Once completely cooled, drizzle with vanilla icing.