Cinnamon-Rhubarb Muffins

A friend from work gave me some rhubarb from her mother's garden... it was chopped and frozen, eating away at me, begging (from inside the freezer) to be baked into something delicious!
I found this recipe on FineCooking.com, but (of course!) have made a few alterations:

Cinnamon-Rhubarb Muffins
The recipe notes that the muffins are best when still warm... I kind of disagree. I sack all of my muffins by two in Ziploc bags and toss them in the freezer to take to work for breakfast/snack, I think the muffins were better after freezing, the flavors became more clearly recognizable.

2 cups flour (I used one cup white and one cup wheat)
3/4 cup granulated sugar
2 1/2 tsp. baking powder
1 tsp ground cinnamon
1/2 tsp baking soda
1/2 tsp kosher salt
1 cup sour cream (I used 1/2 cup Greek yogurt and 1/2 cup sour cream - both fat free)
1 stick (8 Tbsp) unsalted butter, melted and cooled slightly
2 large eggs
1 tsp pure vanilla extract
1 1/2 cups 1/4-inch-diced rhubarb (I used about 2 cups, and felt like I could have added more, though my chunks were larger than the recommended 1/4 inch cube)

For the topping:
3 Tbsp granulated sugar
1/2 tsp ground cinnamon
(I used a premixed cinnamon and sugar shaker that David brought when he moved in and that I now love) :)

Preheat your oven to 4oo degrees. Slice the butter into 1 inch cubes, place in a oven safe dish and toss it in the oven while preheating to melt.

In a large mixing bowl, combine the flour, sugar, baking powder, cinnamon , baking soda, and salt - whisk to blend.
In a medium bowl, whisk together the sour cream, melted butter, eggs and vanilla until smooth. I loved this part, your end result smells like tasty vanilla custard - but no tasting! It contains eggs! :)
Lightly stir the sour cream mixture into the dry ingredients with a spatula until the batter just comes together; do not over mix. Gently stir in the diced rhubarb - your batter will be very thick.
Divide the batter between 12 muffin cups, sprinkle with the cinnamon sugar mix, and then bake until golden brown, 18 to 22 minutes.
When you take the muffins out of the oven, let them cool in the pan for the first 10 minutes or so, this helps them firm up and will hopefully keep all of your rhubarb in the muffin (I did have one casualty!)

These muffins are so good and remind me of my Mom's Rhubarb Cake! Just make sure to use paper muffin cups or Pam with flour baking spray (the one with flour is like a magic trick, nothing sticks!)

I hope you enjoy! :)