Measure out the triple sec, tequila, freshly squeezed lime juice, and simple syrup. Set them aside for quick access.
Fill your blender with the ice, creating a mound that looks like a snowy peak.
Pour the measured tequila, triple sec, lime juice, and simple syrup over the ice in the blender.
Secure the lid and blend on high speed, listening for the whirring sound and watching the mixture turn from icy chunks to a thick, slushy consistency. Stop blending once the texture is grainy and smooth, with no large ice pieces visible.
Optional: Moisten the rim of your glass with lime and sprinkle with salt for a classic touch.
Pour the frozen margarita into your prepared glass, watching it pour in a thick, frosty stream that resists as it fills the glass.
Garnish with a lime wheel or a sprig of fresh mint if desired, and serve immediately to enjoy the icy, textured refreshment.