In a medium saucepan, cook strawberries with 1 tablespoon sugar over medium-low heat for 8–9 minutes until softened and juicy. Remove from heat.
In a small bowl, combine ½ cup cold water and gelatin. Let sit for 5–10 minutes until bloomed.
Using a blender or immersion blender, puree the strawberries until smooth. Strain lightly, leaving some pulp for texture and flavor.
Return the strawberry puree to the saucepan. Warm gently over low heat. Do not boil.
Stir in 1¼ cups water, remaining sugar, and bloomed gelatin. Stir until the sugar and gelatin are fully dissolved. Remove from heat and let cool until warm.
Meanwhile, lightly grease the cake pan and set aside.
Stir in lemon juice and milk. Add between ⅓–⅔ cup milk depending on how pale pink you want the gelatin to be.
Pour the gelatin mixture into the prepared cake pan. Refrigerate for 7–8 hours or overnight until fully set.
To release the gelatin, run a knife around the edges and soak the cake pan in warm water for 1–2 minutes. Invert onto a serving plate and decorate with additional strawberries.