Begin by preparing your glass. Rub a lime wedge around the rim of each glass, then dip the rim into coarse salt or sugar to coat it evenly. Set aside.

In a blender, combine the frozen blackberries, silver tequila, triple sec, fresh lime juice, simple syrup (or agave nectar), and ice cubes.

Blend on high until the mixture is smooth and creamy. Depending on your blender, this may take about 30 seconds to 1 minute.

Taste the mixture to ensure it's balanced. You can adjust sweetness by adding more simple syrup or lime juice for extra tartness if needed.

Pour the blackberry margarita mixture into the prepared glasses, filling them to the top.

Garnish with fresh blackberries or a slice of lime for an extra touch of flair. Serve immediately and enjoy!