Begin by preheating your oven to 350 degrees F. Line a 12-well muffin pan with paper liners and set aside.

In a medium bowl, whisk together the flour, baking powder, baking soda, kosher salt, and ginger. Set aside.

In a large bowl, whisk the granulated sugar, brown sugar, eggs, and lemon zest until well-mixed. Add the oil and milk, whisking continuously until smooth. Gradually fold in the dry ingredients just until blended.

Distribute the batter into the lined muffin wells, filling each about three-fourths full.

Fill a pastry bag with lemon curd and snip off the tip to create a ½-inch opening. Add the curd into the center of each muffin cup until the batter rises to the top edge.  Avoid the bottom and sides. Gently tap the pan on a towel-lined countertop to settle the contents and add any additional curd as needed. Top off with the remaining batter.

For the streusel topping, mix the flour, pecans, sugar,  cinnamon, and kosher salt in a small bowl. Drizzle melted butter over the mixture and stir with a fork until it becomes crumbly.

Evenly sprinkle the pecan streusel over each muffin.

Bake in the preheated oven for about 30 minutes, or until a toothpick inserted into the center comes out clean. Allow muffins to cool in the pan for 10 minutes, then transfer to a wire rack to cool completely.