Preheat oven to 350.
On a foil or silpat lined baking sheet add your bacon and sprinkle with brown sugar, pressing into bacon. Flip bacon over and repeat to other side.
Bake in oven for about 25-30 minutes flipping half way through.
Remove from oven to immediately remove bacon to cooling rack.
Meanwhile turn your oven to 375.
In large bowl mix together your flour, sugar, baking soda and salt.
In another bowl mix together your eggs, milk, sour cream, banana, oil and vanilla, stirring until combined.
Add wet mixture into dry mixture and stir until just mixed.
Spray 2 standard donut pans (or one and work in batches) with non stick cooking spray.
Add your donut mix to a piping bag and pipe into donut pan.
Bake for about 10 minutes or until set and donuts spring back when touched.
Once cooked, remove from oven and transfer to cooling rack to cool completely.
To make your frosting mix together your butter, shortening and peanut butter until blended.
Add in your powdered sugar 1 cup at a time until you reach your desired consistency.
If it gets too thick then add some milk.
In small bowl whisk together your glaze ingredients.
Once bacon has cooled, chop into small pieces.
To assemble, cut your donuts in half.
Add your frosting to a piping bag and pipe over bottom half of donut until covered, repeat for remaining donuts.
Dip the tops of the donuts into the glaze mixture and then place on top of frosting.
Sprinkle with candied bacon and serve.