• Preheat the oven to 375 degrees F (190 degrees C).
• Prepare a standard muffin tin by adding cupcake liners and spraying them lightly with baking spray. Set aside.

To make the banana cupcakes:

• Mash 3 overripe bananas in a small bowl. Add the Greek yogurt, beaten eggs, and vanilla. Stir well to combine. Set aside.
• In a large bowl, blend together the softened butter, white granulated sugar, and brown sugar until thoroughly combined, scraping down the sides of the bowl as needed.
• Pour the mashed banana and Greek yogurt mixture into the bowl with the butter and sugar and blend slowly to fully incorporate the ingredients.
• Use a sieve to sift the flour, baking powder, and baking soda into the wet ingredients. Add the coarse salt to the bowl and gently combine the ingredients, by hand or using a mixer, until no flour is visible. Do not overmix.
• Use an ice cream scoop to fill waiting cupcake liners inside the cupcake tin ¾'s full. Bake in the preheated oven for 25-30 minutes, or until a toothpick or cake tester inserted into the center of the cupcakes comes out clean.
• Remove the cupcake tin to a wire rack to cool for 10 minutes and then remove the individual cupcakes from the pan and cool completely on the wire rack before frosting.

To make the banana caramel buttercream frosting:

• Mash the overripe banana in a large bowl. Add the softened butter, vanilla, caramel and salt. Blend until combined. Gradually, and on slow speed, add the sifted confectioner's sugar into the banana and butter mash until you reach your desired consistency. For thinner frosting, add less sugar. For thicker frosting, add more sugar.
• Pipe the frosting onto cooled cupcakes with a large star tip fitted into a piping bag (or large zip top bag), or pile and spread the frosting onto the cupcakes however you like. Top with sprinkles if desired.