Melt the butter over a warm water bath until fully liquid. In a medium bowl, combine the Oreo cookie crumbs with the melted butter. Stir until every crumb is evenly coated and the mixture resembles wet sand.

Divide this mixture evenly among your serving glasses or molds (about 2-3 tablespoons each).

Use the bottom of a glass or a small spoon to press the crumbs down firmly and evenly to create a compact base. Place the glasses in the refrigerator to chill and set while you make the mousse.

Fill a small bowl with ice water. Submerge the gelatin sheets in the cold water and let them soak for 5-10 minutes. They will become soft and pliable. Once softened, gently squeeze each sheet with your hands to remove all the excess water. Set aside.

In a large mixing bowl, combine the softened cream cheese and granulated sugar. Beat them together on medium speed until the mixture is completely smooth, creamy, and free of any lumps.

In a separate small bowl or measuring cup, heat the milk until it is hot but not boiling. Add the squeezed-out gelatin sheets to the hot milk and whisk continuously until they are completely dissolved and no strands remain. Let this milk-gelatin mixture cool for a few minutes until it is just warm or at room temperature (this is important to prevent it from curdling the cream cheese).

Pour the slightly cooled milk-gelatin mixture into the cream cheese mixture. Beat on low speed until it is fully incorporated and smooth.

Next, pour in the cold heavy cream. Beat on medium-high speed for 1-2 minutes until the mixture thickens, becomes smooth, and holds soft peaks—it should be like a thick, luscious mousse.

Add the strawberry jam and gently fold it in until you have a uniformly pink mousse with no white streaks.

Remove the glasses with the chilled cookie bases from the fridge. Divide the strawberry cheesecake mousse evenly among the glasses, spooning or piping it on top of the bases. Gently tap each glass on the counter to settle the mousse and remove any air bubbles. Refrigerate for at least 4 hours, or preferably overnight, to allow the mousse to set completely.

Once set, carefully unmold the mini cakes. Top with cream topping and decorate with fresh strawberries. Slice or serve whole and enjoy chilled.