For the Macerated Strawberries: Trim the stems off the strawberries. Toss in the sugar to coat. Add the balsamic vinegar. Let macerate until the sugar has dissolved and formed a syrup, about 2 hours.
Remove the strawberries from of the liquid and pat dry. Reserve under refrigeration until needed.
For the Vanilla Gelée: Combine the vanilla pods and the water. Let the vanilla pods cold-infuse overnight.
Bloom the gelatin. Bring 500g / 1lb1.64oz of the infused water to a boil with the sugar to dissolve the sugar. Melt the gelatin by adding it to the hot vanilla water. Stir until dissolved. Pass through a fine-mesh strainer. Add this mixture to the remaining vanilla water.
Fill a half sheet pan lined with plastic wrap halfway with the gelée. The pan should be completely covered with plastic, even the frame. Try to do this on a reach-in refrigerator shelf so that the pan doesn’t have to move too much. Let the gelée set in the refrigerator.
Pat the macerated strawberries dry with paper towels. Place them on the set gelée. Keep the strawberries 5cm / 2in apart from each other. Pour the remaining gelée over the strawberries until it covers the strawberries. If the gelee has set up while setting the strawberries in the pan, warm the mixture slightly to melt the gelatin. Try to do this on a reach-in refrigerator shelf so that the pan doesn’t have to move too much. Let the gelée set in the refrigerator.
Using a 3.75-cm / 1.5-in square cutter, cut out cubes that surround where the strawberries are set in the gelée. Dip the cutter in hot water and pat it dry before cutting each time.
Place each cube on a sheet pan lined with an acetate sheet. Cover with plastic wrap and reserve refrigerated.
Using a paring knife, cut the acetate sheets around the gelée cubes. This will make them easy to handle during service, since it is easier to pick up a sheet of acetate than a slippery cube of gelée. Use an offset spatula to pick up the acetate.