For FAR 23 airplanes not approved for intentional spins - basically a controllability requirement from a delayed stall recovery - recover after one turn (or 3 seconds) of a spin within one additional turn; plus consider the effect of abnormal control actions during that first turn in which a further two turns is acceptable to recover.
Abnormal control actions "The parameters that need to be investigated depend on the design of the airplane as well as on the results of the normal spin tests. These checks include, as a minimum, the following: the effect of ailerons with and against the spin, the effect of elevator applied before the rudder at recovery, the effect of slow elevator release, the effect of entry attitude. Ailerons with and against the spin should be applied at entry and during spins. Elevator and rudder against the spin should be applied during the spin. Spinning should continue for up to three seconds, or for one full turn, while the effects of abnormal aerodynamic control inputs are observed. Apply normal recovery controls as outlined in paragraph c(2)." I have experienced most of those abnormal control actions just doing straight, power off stalls in flight reviews and refresher training with PPLs.
It is quite an extensive test program with different cg positions etc - a pilot can be reasonably confident in using such an airplane as a flight trainer doing all of the stall exercises in Part 61.
Para c(2): "recover by reducing power to idle, if not already at idle, apply full .... rudder followed by forward elevator".
LSA requirements are similar or identical (I haven't looked recently and I'm not familiar with all of their requirements). Difference is that LSAs are self-certified and FAR 23 airplanes are certified by the USA FAA who are extremely knowledgeable and skilled.