Add all ingredients to a high speed blender. Blend on medium-high until completely smooth. This should take around 30 seconds with a good quality blender. Make sure there are now left over chunks. You want it to be very smooth.
As you blend, stop and taste. Adjust your mixture as needed. Everyone has different preferences when it comes to their lemonade. Add more agave/honey/maple syrup for sweetness. Add more lemon juice for tartness, or more strawberries for a more intense strawberry flavor.
Once the strawberry mixture is completely blended and smooth, pour it through a fine mesh strainer to remove any last chunks or strawberry seeds. Transfer into a large pitcher after.
I recommend chilling the strawberry lemonade drink in the refrigerator for at least 30 minutes before serving.
Once ready to serve, stir the drink in the pitcher and then pour over ice. You can add lemon slices for extra lemony punch (and it also looks super pretty!)
*This is a low amount of sweetener, you may want to add more based on your personal preference.