Step 1: Gather your ingredients. Ensure your frozen fruit is truly frozen solid for the best slushie consistency.
Step 2: Add the frozen berries (or your chosen frozen fruit) to a high-powered blender. If using a less powerful blender, you might want to let the fruit thaw for 5 minutes first, but not too much.
Step 3: Pour in the cold water or fruit juice. Start with 1/2 cup; you can add a little more if the mixture is too thick to blend.
Step 4: Add 1 tablespoon of simple syrup. If you prefer a sweeter slushie, you can add another tablespoon or use a natural sweetener like honey or agave. A squeeze of fresh lemon or lime juice can brighten the flavors.
Step 5: Secure the blender lid and blend on high speed. You might need to use the tamper attachment (if your blender has one) or pause and scrape down the sides with a spatula to ensure all ingredients are incorporated and create a smooth, icy mixture. Blend until it reaches a thick, uniform slushie consistency – not too watery, not too chunky.
Step 6: Taste and adjust sweetness or tartness as needed. Add more sweetener or a bit more lemon/lime juice if desired, then blend briefly to combine.
Step 7: Pour immediately into chilled glasses. Garnish with fresh fruit or a sprig of mint, if using. Serve and enjoy your refreshing homemade slushie right away!