Step 1: Gather all your ingredients. Ensure your fruit is thoroughly frozen. This is the secret to a thick, not watery, slushie.
Step 2: Add the frozen strawberries, frozen mango chunks, orange juice, and water to your Ninja blender pitcher. If using, add 1 tablespoon of honey or maple syrup now.
Step 3: Secure the lid on your Ninja blender. Start blending on a low setting, then gradually increase to a high setting. You may need to use the 'pulse' function or the tamper (if your model has one) to push the frozen fruit down towards the blades.
Step 4: Blend until the mixture is completely smooth and has a thick, slushie-like consistency. If it's too thick to blend, add a tablespoon of water or orange juice at a time until it blends smoothly, but avoid adding too much liquid, or it will become too runny.
Step 5: Taste the slushie. If you prefer it sweeter, add the remaining tablespoon of honey or maple syrup and blend for a few more seconds until combined.
Step 6: Pour the freshly made slushie into chilled glasses.
Step 7: Garnish with a fresh mint sprig, a slice of strawberry, or a small piece of mango, if desired. Serve immediately and enjoy!