I've seen many latching circuits through searching and reading some simple circuits. Most use NPN+PNP combination, some bistable ones use two NPNs, some use DPDT relays.
Is the following circuit going to work as a latch?
The idea is that after the momentary switch is pressed , load is supplied through N-Mosfet as well as the NPN transistor(which will hold the N-Mosfet gate high until a reset occurs in power)
(Sorry, had to hand-draw as the circuit editor doesn't let me make a circuit on mobile phone)