2cupsunsalted butterroom temperature, cut into 1-inch pieces 452g
1tspvanilla extract5mL, optional
For the Raspberry Reduction:
6ouncesraspberries
2TBSsugar
2tbslemon juice
1TBSwater
Instructions
For the Cupcakes:
Heat oven to 350F, 177C. Sift together the dry ingredients and give them a good whisk.
Cream the butter, peanut butter and sugar, then mix in the rest of the wet ingredients, eggs, milk, vanilla etc.
Slowly add the wet ingredients to the dry, mixing until just combined.
Fill cup liners about 2/3 the way up and place in middle rack of oven for about 20-25 minutes or until the centers are springy.
For the Raspberry Reduction:
Place the ingredients in a small sauce pan on medium low heat.
Mash the berries with the back of a spoon or muddler and stir occasionally.
You want to reduce the amount of liquid, intensify the flavor, and thicken the liquid so aim to cook until the mixture is reduced by half.
Strain the reduction and set aside to cool.
For the Italian Buttercream:
Beat the egg whites and 1/3 cup of sugar until soft peaks form.
In a medium saucepan add the remaining sugar and 1/3 cup water and place on low heat.
Stir constantly until sugar melts and becomes clear. Maintain a medium high heat until temperature reads 240F.
Drizzle the sugar into the mixer immediately. Run mixer until meringue is room temperature.
Add room temperature butter into running mixer one piece at a time. Beat until butter is combined and mixture has reached a silky consistency
Mix in the cooled berry reduction and pipe onto cupcakes (I used an 869 tip).
Notes
If your buttercream is "soupy," just pop it into the fridge for a couple of minutes, then beat it. It should thicken up. I find consistency problems arise mostly from the meringue being too warm when the butter is added. Chilling it will help improve the consistency.
If you want to really pump up the flavors, you can make this into a filled cupcake to which you could add a peanut butter ganache or jam.
You can substitute whole milk yogurt for the sour cream if desired, I do it all the time and can’t really tell the difference.
Instead of a raspberry reduction you can use the juice from thawed raspberries, or even your favorite jam.