Start by making your crust. Mix 1/4 cup crushed graham crackers with 2 tablespoons melted butter until it resembles wet sand. Press a small amount into the bottom of each of your 6 serving cups. Pop these in the freezer while you work on the mousse—this keeps them from getting soggy.
Pour 1/4 cup milk into a small bowl and sprinkle the gelatin over top. Let it sit for 2 minutes so it blooms. Heat it for about 15 seconds in the microwave (don't skip this step or it won't dissolve properly). The mixture should look clear, not cloudy.
Blend 2 cups fresh strawberries with 1 tablespoon lemon juice and 1 tablespoon honey until smooth. Press the mixture through a fine mesh strainer to remove seeds—yes, really, this makes the texture way better. You should have about 3/4 cup strawberry puree.
In a separate bowl, whip 1 cup heavy cream with 1/2 cup sugar until stiff peaks form (about 2-3 minutes with an electric mixer). This is where your strawberry mousse cups cozy gets that cloud-like texture. Add a pinch of salt and 1 teaspoon vanilla powder to the whipped cream.
Gently stir your gelatin mixture into the strawberry puree. Let it cool for about 1 minute so you don't cook the whipped cream. Fold the strawberry mixture into the whipped cream using a rubber spatula—fold gently in thirds, don't stir aggressively.
Spoon the mousse into your prepared cups over the graham cracker crust. Smooth the tops with the back of a spoon. Refrigerate for at least 3 hours or until the mousse is completely set and jiggles only slightly when you move the cup.
Top with fresh strawberry slices or a small dollop of whipped cream right before serving. Mine always looks a little prettier after a quick garnish, but honestly the flavor's already there without it.