Its hard but doable if they aren't very good. You should have a bit of silence-free time because they'll inevitably just open with Avenger's Shield.
If they're already on you, fear early to open up a gap, then Immo>Incinerate>Incinerate>Conflag for slow. The travel time on Incinerate is really nice for casting it in fears, since the Immo itself wont break it right away.
After this, kite a bit and get another Incinerate or two in. Fear around when your Conflag slow is ending instead of reapplying it. They'll probably be hitting the health range where they remember to click their heals, so this fear should interrupt a FoL. Incinerate > Immo > Fear in this one. By the time your fear finishes casting, theirs will be broken and they'll be casting another heal out of it. Then Incin/Conflag/Conflag and hope for a crit or two to finish them off.
Pop Dark Regen around half health and use your healthstone as needed, preferably while Dark Regen is still active.
Its pretty easy to counter this, but difficult concepts like covering your heals with Avenger's Shield seem to elude most of our precious Prot Paladins. Its also a lot harder to pull off inside when your Fears can LoS them around corners. This works like a charm against terrible Holy Pallies casting Holy Shock offensively too
