Different cultures have creme brulee with hard or soft tops. I like them crackable
Make the toffee/caramel tops separately some hours earlier, and store in an airtight container
When ready to serve. Line up all the creme's. Have one person carefully placing the tops, while a second person uses the largest torch you have to just blast the middle to cause it to stick to the creme. Fifty can be done in a few minutes just before serving
It just a mater of finding 3 x 4 muffin tins or similar as molds, with the same base size or slightly smaller than your ramekins tops
For an artistic look, make large very thin sheets of toffee/caramel and shatter them into pieces. Poke a couple of large pieces just into the creme at a slight angle to the surface, and then finish with scatter of smaller pieces and crumbs. A very short blast of a large torch will set them in place. much more interesting
Or go overboard and blow some toffee/caramel balls the right size the day before, and use a hot wire cutter (used to cut polystyrene packaging) to make a half sphere to place on top, or invert and fill with creme! (store sugar balls in airtight containers etc...)