Preheat oven to 425 degrees F. Butter or spray a 12-count muffin pan with oil or line with cupcake liners. Set aside.
In a large bowl whisk the flour, baking soda, baking powder, chi spice and salt.
Using a handheld mixer or stand mixer fitted with a paddle attachment, beat the oil and sugars on high speed until smooth and creamy, about 2 minutes. Scrape down the sides and bottom of the bowl as needed. Add the eggs, sour cream, maple, vanilla and apple cider. Continue to beat on for 1 minute until fully combined. Turn the mixer down to low speed, and carefully add the dry ingredients into the wet ingredients. Scraping down the sides of the bowl as need, mix until no more pockets of flour remain. Gently fold in the apples.
Make the streusel. In a small bowl, combine the brown sugar, oats, flour, melted butter, cinnamon, pecans if using and a dash of salt. Stir with a fork until all the clumps of brown sugar are incorporated and everything is mixed well.
Spoon the batter evenly into the prepared muffin pan, filling the cup mostly to the top. Once all the muffins cups are filled, sprinkle the streusel evenly over the top of the muffins. *If you have extra batter leftover for a few more muffins, leave some extra streusel aside to top them*
Bake the muffins in the preheated oven at 425 degrees F for 5 minutes. After 5 minutes, reduce the temperature to 350 degrees F and bake until a tester comes out clean, about 15-18 minutes. Remove the muffins from the oven to cool. While the muffins are cooling, start on the brown butter glaze.
In a small saucepan over medium high heat add the butter. Whisk for 5 minutes, until the butter turns a deep brown and has a 'nutty' aroma. Remove from the heat and allow to cool for 5 minutes. After the butter cools, whisk in the powder sugar, vanilla, and a pinch of salt. *If the glaze is too thick to drizzle, add 1 tablespoon of water at a time until you reach the desired consistency*. Once the muffins are completely cool- drizzle the glaze over the tops, serve and enjoy!