Combine strawberries, honey, and mint leaves in a small saucepan; bring to a simmer over medium-high heat. Cook and stir until honey dissolves, 1 to 2 minutes.
Pour mixture into blender.
Pour the sauce into a blender, filling the pitcher no more than halfway full. Hold down the lid of the blender with a folded kitchen towel, and carefully start the blender, using a few quick pulses to get the sauce moving before leaving it on to puree. Puree in batches, if necessary, until smooth. Alternately, you can use a stick blender and puree the sauce right in the cooking pot.
Strain sauce through a fine mesh sieve. Stir in lemon juice.