Grab a large pitcher and add all your ingredients: pineapple juice, lime juice, coconut milk, Grand Marnier, agave syrup, and blanco tequila.
Stir or shake well until everything’s combined and creamy.
Chill it in the fridge for at least 30 minutes to let the flavors settle in.
When you’re ready to serve, run a lime wedge around the rims of your glasses and dip them in Tajín.
Fill with ice, pour in your margarita mix, and top with a lime slice.