Cut the pineapple into big half-ring slices/chuncks. Place them in a 1-gallon or more jar, along with the whole jalapenos and fill with the tequila. Let age for at least 2 weeks.
When properly aged, fill a cocktail shaker with ice, lemonade, lime juice, and 1 to 2 oz of the pineapple-jalapeno infused mixture (depending on taste). Shake, and pour in a chilled, salt rimmed margarita glass. Garnish with slice of lemon, lime, and a small jalapeno ring. Enjoy this sweet and spicy refreshing margarita!