I think you answered your own question. If your "tinder" burned for 11 minutes, a teaspoon is too much.
I don't use Vaseline. I use charcoal lighter, and I find about 1/8 teaspoon (ten drops) applied to a small roll of fiberglass in the bottom of my stove reliably starts dry 1/8" diameter twigs. About 3/16 teaspoon will start them even if they're wet.
I'll bet you'll get the same results with similar quantities of Vaseline