a state of super excitement about an event or activity. An advance on the phrase keen bean as the thought of bees on toast makes it more extreme and dangerous.
Example 1:
Boy: Want to go out drinking?
Girl: I am keen as bees on toast to have a night out drinking.

Example 2:
"Michelle is keen as bees on toast for some gherkins"
by KeenBee March 28, 2010
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