Preheat oven to 350° and prepare cupcake pan. Place 1-2 liners in each cupcake tin, spray with non-stick or spray oil. (May use one regular cupcake and one mini-cupcake pan if desired; makes 12-18 regular sized cupcakes or 12 regular, 12 mini)
In a large mixing bowl, mix together dry ingredients with a whisk. Flour, cocoa, sugar, baking soda, baking powder. Add to the dry mixture all wet ingredients; butter, egg white, egg, vanilla, sour cream and milk, mix on low until blended and semi-smooth, but don't over mix, there will be some lumps (mostly bits of butter). May mix using a stand mixer or hand mixer.
Using a scoop, pour cupcake batter into prepared liners, filling slightly more than half way. Baking 18-20 minutes until tops spring back when lightly touched, 14-18 minutes for mini-cupcakes.
Allow to cool for 1-2 minutes in the pan on a rack, then carefully remove from pan to a cooling rack. Cool completely. While cooling, prepare your chocolate ganache.
In a medium-sized microwave safe bowl, place in your chocolate chips, butter and whipping cream. Microwave on high in 30 second intervals, stirring or whisking well after each 30 second heating. It should only take a few 30 second heatings to melt. If in doubt, whisk a bit longer and it will continue melting as you whisk. Set aside to cool for a few minutes to thicken slightly, or in fridge will thicken more.
Meanwhile, using an apple corer or cupcake corer, or a narrow spoon (a grapefruit spoon might work here), remove a small core from the center of the cupcakes, reserve cores. Using a spoon or pour ganache into a sandwich baggie and snip off end, squeeze or pour ganache into the center hole of the cupcakes. If desired, using the tip of the reserved cores, replace on top of the hole, not necessary, but makes a smooth surface.
At this point, the cupcakes may be refrigerated or frozen in airtight containers until ready to frost. When ready to frost, remove from freezer while making frosting.
RASPBERRY BUTTERCREAM
In blender, puree the raspberries until smooth, pour through sieve, into a small saucepan. Using a spatula, press the puree through the sieve, capturing the seeds in the sieve. Be sure to scrape off any puree hanging to the bottom of the sieve. Discard seeds. Heat raspberry puree over low heat, stirring occasionally and bring to a simmer. Allow to simmer until reduced about 10-20 minutes. It should reduce to about ¼ - ⅓ of original volume, it should be thick, like jam when finished.
Place puree in fridge or freezer to chill completely. If placing in freezer, stir occasionally. In a large bowl of a mixer, beat the butter until light and fluffy on medium-high, about 2-3 minutes. Scrape down sides. With the mixer on low, add 2 cups of the powdered sugar, increase the speed and mix on medium-high for 1 minute. Beat in 2-3 tablespoons of the chilled* raspberry puree and the salt (if not using salted butter). *Be sure the puree is completely chilled before adding so you don't melt your frosting.
Once raspberry puree is mixed in, scrape down sides and add additional powdered sugar, 1 cup at a time to desired sweetness and texture. Mixing on low to incorporate sugar, then increasing to medium-high. Lastly, add the whipping cream and beat on medium-high for an additional 1-2 minutes until the frosting, is light, fluffy and all ingredients are incorporated. Transfer frosting into piping bag with round tip (I used a Wilton 1A). When ready to frost cupcakes, using steady pressure, pipe on frosting in a swirl motion, starting from the outside in and upward.
Cupcakes may again be refrigerated at this point in an airtight container for up to a day. Just prior to serving if desired, garnish with a fresh raspberry (washed and dried), some sprinkles, silver dragees and/or a chocolate heart or letter.* (See Notes)
Notes
Please be sure to follow all instructions on cooling, if not your frosting will melt and slip right off your beautiful cupcakes!TIP | If you don't have time or desire to go through all those steps for the fresh puree, you may replace the raspberry puree with a good quality raspberry jam. Reduce your sugar slightly to adjust for the sugar in the jam.Chocolate Shapes: Melt ¼ cup semi-sweet chocolate chips or discs in microwave safe bowl 20-30 second intervals stirring between until melted. Pour melted chocolate into baggie, snip off a teensie bit of the corner and pipe desired shapes on a wax paper or parchment paper lined cookie sheet. Allow to harden completely before carefully peeling off paper. May be refrigerated or frozen to speed up the process.