Jalapeño-infused simple syrup: Bring ¼ cup of water to boil in a small saucepan. Add sliced jalapeño and ½ cup sugar and stir until the sugar dissolves. Turn down the heat and simmer about 5 minutes. Remove from heat and let cool. Refrigerate overnight if possible. (If needed same day refrigerate at least 30 minutes - 1 hour).
Add simple syrup, lime juice, tequila, triple sec, and blueberries to shaker.
Muddle blueberries.
Add ice, shake, and strain into a glass with ice.
Garnish with lime wedge, jalapeño slice, and more blueberries if you wish.
Recipe by Cuisine & Cocktails at https://www.cuisineandcocktails.com/blueberry-fire-margarita/