This crowd-pleasing frozen drink is the ultimate warm-weather party recipe — just three ingredients and a Ninja Slushi machine stand between you and a refreshing spiked slush. Taking cues from the light, bubbly drinks beloved along the French Riviera, lager beer and lemonade come together with a splash of grenadine for a sweet, bubbly, and slightly tart sip that goes down easy. Pour into a pint glass and enjoy straight from the machine.