Way to build my own custom MIUI 7 lollipop-based rom

Hi,

I'm currently owning a togari (C6802) device running a MIUI 7 ROM.
It's a very nice rom and I'm considering sticking with it, but I'm missing my good old lollipop flavour.

I'm looking for a way to build my own custom MIUI 7 lollipop-based rom.

What would be the better way to do so ?

Thanks in advance for your advices,
Kushang