Add the strawberries and rum to the bottom of a cocktail shaker. Muddle with a drink muddler or the end of a wooden spoon until the strawberries are fully mashed.
Add lime juice, orange liqueur, simple syrup, and orange bitters.
Fill shaker half-way with ice and cover. Shake vigorously for 30 seconds.
Double strain into rocks glass or stemless wine glass with large sphere ice. Garnish with lime wheel or strawberries, if desired.