Trying to hit to their BH when they are over there, can end up spraying the shot wide. Trying to hit to the open court leaves you open to their best shot.
From the above I assume, you are already in a slightly defensive position at this point (or otherwise you could have hit a hard one down the line to their forehand).
1. The best option is NOT to get into this slightly defensive position. This is done by infact hitting deep through the middle early in the point, so that their backhand is accessible to you, when you are in neutral. And you get a weaker shot from their backhand.
2. Even if you get into this slightly defensive position where they are not hitting strong forehands to your backhand, what you don't want to do is trying to get to their backhand. Of course you need to realize that your main task at hand is to neutralize and get back into a neutral position (instead of thinking about hurting them). This is done by high trajectory deep balls, especially to their forehand side. All you are trying to do is NOT let them jump on it and finish, and possibly open up their backhand. If you have to, hit multiple neutral loopy shots to their forehand (either through middle or to duece court). Eventually when you get chance force a stronger shot to, now available open space in their backhand.
Essentially, to get space on their backhand, you have to hit to their forehand. When you hit to their forehand, attack is probably not your main intent, the main intent is them not being able to attack (so that you get a neutral ball back).
Arguably their forehand attack should be better than yours (since you are playing at same level, and they have a weaker backhand than you). This is why you may want to get into a forehand battle with them, instead keep it neutral on forehand to open up backhand. Once you have upper hand everything goes (attack to forehand wing or backhandwing).