Much before Pardon's beautiful result https://arxiv.org/abs/1906.05816 that any compact CW-orbispace (=topological stack) with finite isotropy groups is of the form $[M/G]$ for $G$ a compact Lie group,

I had shown in joint work with David Metzler https://arxiv.org/abs/math/0302182 (Thm 5.5 and 5.7) that it is of the form $[[M/G]/H]$ for $G$ and $H$ compact Lie groups.