My two favorites are double wrist control, hipping to one side to shed/pass one arm with your knee across their arm/chest then hipping the other way to finish the triangle.
The other is from rubber guard, lock up 'mission control' as bravo calls it, then reach over your leg on their neck with your other arm gripping their gi or lat. Once there, use your free elbow to pass the arm and get your leg over for the triangle. If they try to shove their arm through, you have an easy arm bar, if they don't, finish the triangle.