Preheat the oven to 375 degrees F. Line a muffin tin with liners.

Make the crumb first so it’s ready. Whisk together the sugar, cinnamon, salt and melted butter until combined. Whisk for a good minute or two until the sugar begins to dissolve, then use a wooden spoon to stir in the flour. The mixture will be crumb-like and dry. Almost like sludge or sand. This is what you want! Set it aside until you’re ready to use.

In a small bowl, whisk together the flour, baking soda, salt and cinnamon.

In a large bowl, whisk together the sugar and the eggs until combined. Whisk in the apple butter. Whisk in the oil, yogurt and vanilla extract until smooth.

Stir in the dry ingredients until just combined - do not overmix!

Fill the muffin tins about ¾ of the way full. Sprinkle the crumb over the top of each. Bake the muffins for 20 to 22 minutes, or until set in the center. Let cool before serving!