• Taste the apples before beginning this recipe. The apples should be tart and crisp. Mushy apples won’t hold their shape in these muffins.
• Preheat the oven to 350°F (180°F) and toasted the pecans for 5 minutes. Remove them from the oven, let them cool for 10 minutes, then coarsely chopped them.
• Increase the oven temperature to 425°F (220°C) and line a 12-cup muffin tin with tulip muffin liners.

Make the Pecan Streusel

• In a small saucepan, melt the butter over medium heat. If the butter starts to pop, reduce the heat to low. While the butter is melting, place the flour, brown sugar, ground cinnamon, and salt in a small bowl and whisk to combine.
• Add the warm melted butter and use a fork to combine the ingredients until the streusel has a sandy texture. Add the chopped pecans and mix in. Refrigerate the mixture until ready to use.

Prep the Apples

• Peel the apples. With the apples in the upright position and the stem pointing skyward, cut down and around the cores to remove the flesh in 4 lobes (you’ll be left with a square-shaped core). Set the lobes flat-side down and cut the apples into cut into 1/2-inch cubes.
• Toss them with 2 teaspoons of sugar and 1 teaspoon ground cinnamon. Set this mixture aside.

Make the Muffin Batter

• Melt the butter over medium low heat and set it aside to cool to 85°F. Do not add hot butter to the batter.
• Place the flour, baking powder, and salt in a medium bowl. Whisk for about 30 seconds to thoroughly combine.
• Place the sugar in a small bowl, and zest the orange directly onto the sugar. Use your fingers to rub the zest into the sugar until it is fragrant and the sugar turns orange. Pour the sugar-orange mixture into a large bowl.
• Add the spices to the sugar and whisk until well combined. Add the eggs and whisk for 1 minute until the batter feels thin and loose (it will initially feel a little stiff), and is a little lighter in color. Whisk in the melted butter, then whisk in the sour cream and vanilla extract.
• Add the flour mixture in 2 batches to the wet ingredients and use a large spatula to gently mix until it is incorporated. The batter will be lumpy. Let the batter sit for 15 minutes.
• Drain the apples. There should be about 2 tablespoons of liquid. Add the apples and 1 tablespoon of the liquid, and use the spatula to fold them into the dough. The batter will be thick.

Bake the Muffins

• Divide the batter evenly between the muffin cups, about 85 grams per cup. Place about 2 tablespoons of streusel topping on the top of each unbaked muffin and lightly press it into the batter.
• Bakes the muffins for 5 minutes at 425°F (220°F), then without opening the oven door reduce the temperature to 350°F (180°C) and bake for another 15-18 minutes until the muffins are risen, slightly firm to the touch and an instant-read thermometer registers 205°F (96°C). If you don’t have an instant-read thermometer, insert a toothpick. If there are no crumbs or just a few crumbs, the muffins are done.
• Remove the muffins and allow them to cool for 5 minutes in the muffin tin, them remove them from the muffin tin and place them on a cooling rack. The muffins are best in eaten within the first 2 days.

Storing the Muffins

• The muffins can be stored at room temperature for up to 2 days in an airtight container. Then refrigerated for up to another 4 days in an airtight container or each muffin wrapped individually in plastic wrap.

Freezing the Muffins

• You can also freeze the muffins. Individually wrap each muffin in plastic wrap, then store them in a freezer bag and freeze for up to 1 month.