Something to keep in mind is that traditional muhamara is actually a nut spread, rather than a pepper spread per se. For anyone interested in trying this, there's a full recipe in Hussien Dekmak's The Lebanese Cookbook:
Oil for deep frying
1/2 cup pistachio nuts
1 cup walnuts
1/2 cup cashew nuts
1/2 cup blanced almonds
1/2 cup pine nuts (optional)
2 tbls finely choped onion
1 red bell pepper, seeded and finely chopped
1 tbls finely chopped flat-leaf parsley
4 cups fresh bread crumbs
1 green chile, finely chopped
1 cup olive oil
Salt and black pepper
Heat the oil in a deep fat fryer or deep, heavy-bottomed saucepan. Deep fry the nuts for a matter of minutes---any longer and the walnuts will taste bitter. Drain and set aside to cool.
Finely chop the nuts and place in a bowl with the onion, red pepper, parsley, bread crumbs, chile and olive oil. Season with salt and pepper and mix well.
Personally, I leave out the pine nuts, and char-roast both the bell pepper and green chile. And I increase the bells to two, cuz I like their flavor so much.