No problem, you're thinking. Brandy burns at such a low temperature, you can play snapdragon with your combustible dessert.
And snapdragon is a lot of fun.
But the plum pudding you're imagining is decorated with holly leaves. Maybe freshly cut holly leaves, maybe dried, maybe--and this would be interesting--plastic.
Igniting your combustible dessert won't burn your fingers, but it will get your holly leaves going in a very serious way, as we discovered a couple of years ago. Your flaming holly leaves could, theoretically, get other things going, too.
Take the holly off and put it well aside before you light the brandy.
Live a long time.
And Happy Yule.