Place the blood orange slices, mint, and bitters into the bottom of a cocktail shaker. Use a muddler to gently crush the oranges and mint to release the juices.
Fill the shaker halfway with ice and add in the bourbon, blood orange juice, and simple syrup. Then gently shake until combined and chilled.
Strain into a glass with crush ice and top with soda.
Garnish with a blood orange slice and fresh mint and enjoy!!