Preheat the oven to 375°F and line a 12-cup muffin tin with paper liners.
Make the pistachio crunch: mix the chopped pistachios, flour, brown sugar and salt with the melted butter until clumpy, then set aside.
Pulse the pistachios with the sugar in a blender for 20-30 seconds, until they form a fine, sandy meal. Transfer to a large bowl and whisk in the flour, baking powder, baking soda and salt.
Add the cottage cheese, eggs, melted butter, vanilla and almond extract to the blender and blend until smooth, 30-45 seconds.
Fold the wet mixture into the dry ingredients just until combined, then fold in the white chocolate chips.
Divide the batter among the cups and pile the pistachio crunch on top of each muffin.
Bake for 20-23 minutes, until golden and a toothpick comes out clean. Cool completely on a wire rack.
Microwave the white chocolate chips with the coconut oil in 20-second bursts, stirring between each, until smooth. Drizzle over the muffins and let set.