First, preheat your oven to 350°F and melt your butter in a microwave mixing bowl in 30 second intervals until completely melted.
Add the rest of the wet ingredients (eggs, olive oil, canned pumpkin, and maple syrup) to the mixing bowl. Use an electric hand mixer to combine.
Then beat in brown sugar until completely mixed.
Once wet ingredients are mixed, add dry ingredients to the bowl (flour, salt, baking powder, baking soda, pumpkin pie spice, and cinnamon). Leave out the butterscotch chips for now.
Mix batter thoroughly. You want to be sure no flour clumps remain and ingredients are completely combined. I really recommend a hand mixer as using a whisk isn't as thorough.
Once your Butterscotch Pumpkin Muffin batter is smooth throughout, add in butterscotch chips and stir.
Distribute batter evenly between 12 muffin liners in a muffin tin. The muffin liners will be close to full (these are bakery style muffins and we want them to have large tops). Add additional butterscotch chips on top.
Bake muffins for 22-27 minutes until they have risen and a tooth pick inserted comes out completely clean.
Once your Butterscotch Pumpkin Muffins are finished baking, melt butterscotch chips and drizzle on top of muffins if desired and enjoy!