Begin by making the cinnamon sugar pieces to add to the dough. Stir together the melted butter, brown sugar, and ground cinnamon. Spread out into an even layer on a small pan lined with wax paper or parchment paper. Place the pan in the freezer for at least 30 minutes to solidify.

Preheat the oven to 400℉. Line a large baking sheet with parchment paper.

In a mixing bowl, whisk together the flour, sugar, and baking powder. Work the cold cubes of butter into the flour mixture using a pastry cutter until the pieces of butter are the size of peas.

Once the butter/sugar/cinnamon mixture is firm, transfer to a cutting board and chop into small pieces. Stir the cinnamon sugar pieces and chopped rhubarb into the flour/butter mixture.

In a separate bowl, whisk together the whipping cream, egg, and vanilla extract until combined. Add to the rest of the ingredients and stir with a spatula until the mixture begins to come together before turning the mixture out onto the countertop and gently kneading/folding the dough together until a dough forms.

Separate the dough into 3 pieces and form each piece of dough into a round around 4 inches in diameter and 1 inch thick. Use a sharp knife to slice each round into 4 quarters. Place the scones on the prepared baking sheet leaving room between each scone to allow them to spread out. Sprinkle the top of each scone with a little bit of white sugar.

Bake in a preheated oven for 14-18 minutes until golden brown. Remove from the oven and allow to cool slightly before serving. Enjoy!