If you read the profile of BPS President Edward Egelman in the BPS Newsletter earlier this year, you know that in his spare time, he is an avid cook. We have asked him to share a recipe with readers here. In keeping with the end of summer in the US, Egelman has chosen to share a grilled dish. 
After being asked to contribute a recipe to this blog, I realized how hard it is to choose one particular dish when I am constantly experimenting with food (at home, that is, and not in the lab!). My son, a computer scientist at Berkeley, introduced me to xanthum gum, which is now a staple in modernist cuisine (or molecular gastronomy). It turns out that this polysaccharide has been mainly used in industrial applications, such as thickening mud for oil drilling, and the total production of it exceeds 30,000 tons a year. It gets its name from the bacterium that produces it, Xanthomonas campestris, which uses it for adhesion to plant cells. Since this is the Biophysical Society (and not a cooking blog) I can add that this hydrocolloid is built from pentasaccharides, with a typical molecule having ~ 7,000 pentamers. It is tasteless, and has amazing thickening properties, leading to sauces with a texture that cannot be achieved with other thickeners, such as flour or corn starch. I might also add that biopolymers of all sorts will be the focus of the Thematic Meeting that we are holding in Rio de Janeiro at the end of October, “Polymers and Self-Assembly: From Biology to Nanomaterials.”
The other night I grilled six boneless chicken thighs, tossed with fresh rosemary, salt, pepper, and olive oil. While they were grilling I sautéed a whole diced onion in olive oil. I then added 200 ml of chicken stock (I typically make ~ 30 liters of this at a time, so it is always available in my freezer). This was seasoned with salt and pepper and reduced over very high heat to perhaps half the original volume. I then added ~ 30 ml of cream (two tablespoons), about the same quantity of a good Dijon mustard, and a small pinch of xanthum gum (perhaps 150 mg, but who has a precision balance in the kitchen?). I pureed this with an immersion blender, necessary to fully dissolve the xanthum gum. If you do not have an immersion blender a regular blender would be fine. The chicken thighs and the sauce were kept warm while I finished the kale. I had previously blanched in boiling salted water perhaps two liters of fresh kale leaves. These were only boiled for about a minute, and then rinsed in very cold water until cool. They were then squeezed quite thoroughly in a colander to remove all water. To finish, the kale was sautéed in olive oil to which some chopped garlic and jalapeños had been added.
The presentation was simple: spread the kale leaves on a warmed plate, place one or two (depending upon the size of the thighs, the number of other courses, and the appetite of the recipient) chicken thighs on top, and then pour the sauce over the chicken. A sprig of fresh rosemary on top of the thigh is all this now needs. Bon appétit!
-Edward Egelman