As the front man of rock band Modest Mouse, Isaac Brock makes music that is simultaneously caustic and elastic. Anyone who has witnessed his aggressive string bending and general instrument strangulation onstage may be surprised by the delicate touch he applies to food preparation. Brock loses himself in food, the act of cooking providing a temporary respite from the noise of his chosen career.

Tonight Brock is preparing tilapia, a fish native to Africa but now grown mostly in South America. This particular cut was raised hormone-free in Ecuador and purchased from Whole Foods. Brock simmers the fish in coconut sauce. The main course is complemented by cumin-spiced black beans, cumin-coconut rice, and a dish of his own creation he calls “cabbage crunch.” His fiancée, Naheed Simjee, has mixed a robust guacamole for predinner snacking. For dessert, I have brought along homemade chocolate chip cookies. Since there was no butter to be found in my refrigerator, I made a substitution of applesauce.

While the meal simmered, Brock offered this disclaimer: “Try to remember this… my cooking is all based on a series of fuckups.”

—Brian J. Barr

I. “I HAVE ALL THESE MUSHROOMS, RIGHT? WHAT AM I GOING TO COOK THEM IN?”

THE BELIEVER: How long has cooking been a passion?

ISAAC BROCK: Since I was in sixth grade.

BLVR: What was it that got you interested?

IB: I remember making this dessert called “Floating Islands” or something. It was kind of a weird, runny, custard-type thing with meringue floating around in it. I remember it being really good, but really gross at the same time—kind of goopy.

BLVR: What was the reason for making it?

IB: No reason. I was just making it for the hell of it. I was going through a cookbook at that point and it just seemed like an interesting one to try.

BLVR: Do you get most of your recipes from cookbooks?

IB: Not anymore. Usually I just steal people’s ideas from restaurants. I’ll go somewhere and eat something and I’ll try and figure out what was in it. Or I’ll try and engineer shit. Buy a bunch of ingredients. I’m really scattered when I shop at the grocery store, so I’ll just be grabbing stuff at random, trying to figure out how it’ll all come together. Like, I have all these mushrooms, right? What am I going to cook them in? I’ll cook them in, say, orange juice concentrate and Bragg’s Liquid Amino Acids.

BLVR: Are you against following recipes?

IB: Sometimes you have to follow recipes. When it comes to baking things, you can’t ad lib how much baking soda or baking...