A/ "Set Standard"
B/ "Standard Cross-Checked (ideally whilst making the sign of an X with the arms) passing flight level xxx now"
A/ "Check" (or "Checked" if you wish to add an extra flourish)
B/ "But.. I already did a cross-check"
A/ "Check"
B/ "Why not, it's free.. Check, Check Check"
A/ "Check"