I made the cake why the bubbles big rough, not fine enough it!

1, the meringue and egg yolk paste is not fully mixed, so that there is a relatively large mass of meringue inside, no batter to help stabilize the state after the heat, delicate meringue bubbles break after the formation of large bubble holes.

2, the degree of whipping of the meringue is not enough, or the cake batter has been placed too long, has begun to defoam back to the liquid state.

3, the oven on the fire is too high, resulting in baking when the top quickly sealed, part of the gas did not go out in time, in the internal formation of large bubble holes.