Measure all ingredients before blending. If using fresh peaches or raspberries instead of frozen fruit, chill them beforehand to keep the smoothie cold and thick. Remove pits from the dates and chop them into smaller pieces so they blend easily.
Pour the soy milk into the blender first. Then add the yogurt, raspberries, peach slices, chia seeds, chopped dates, and salt. Placing liquids at the bottom helps the blender move frozen fruit smoothly.
Blend the mixture on high speed for about 45–60 seconds until the smoothie becomes completely smooth and creamy. The chia seeds will begin to absorb liquid and slightly thicken the drink. If you prefer a thicker texture, add ice cubes and blend again briefly.
Pour the smoothie evenly into two glasses. For presentation, sprinkle a few extra chia seeds or fresh raspberries on top. Serve immediately while chilled and creamy.