Wild Mushroom Ketchup

If you have an excess of wild mushrooms you want to preserve, my tried and true mushroom ketchup recipe might be just the thing you're looking for. It's an old mushroom condiment with a rich flavor like soy sauce crossed with mushrooms.

Have you ever run up to a massive chicken of the woods mushrooms or a hen, only to find it just a tiny bit past being good for the pan? Ever thought there might be something useful you could make with all the edible mushroom biomass you walk past, but pass up? Enter mushroom ketchup.

Mushroom ketchup is one of the original ketchups (also called catsups), all of which probably got their name from an Asian fish sauce called ketsiap. A couple hundred years ago, ketchup was basically a sort of catch all name for different liquid condiment, and you might have ketchups made from grapes, walnuts, or all kinds of different things.

Mushroom ketchup, is one, if not the best known (and still enjoyed) sauces in the family. I'd heard of it, as it's fairly well-referenced in cookbooks around the turn of the 20th century in a number of books I've read, but I didn't make my first batch until about 4 years ago, a time when I was going through 80-100 lbs of mushrooms a week--a great time to start working on a recipe.

I'd seen the Townsend video many people reference now, and although I love historical cooking videos, there was a problem: at that time, there wasn't a single recipe online, and the only mushroom ketchup recipes I could find didn't include specific proportions of salt.

Let me tell you, seasoning to taste with salt, is fine, but something like "a few spoonfuls of salt" can be interpreted vary differently from one person to another (a pet-peeve chef tic of mine). One of my old line cooks made a ketchup from dryad saddles and, while it tasted excellent, it was so salty it made the water I used to chase it down taste sweet.

When making condiments, measuring your salt with a scale can mean the difference between something tasting ok, and your friends saying "you should bottle and sell that".

First, I ordered a bottle of commercial catsup online to gauge the flavor before I set off on my own. Then, for my first couple batches of mushroom ketchup, I had my cooks save the stems and season them with 3% of their weight in salt and leave them in the cooler.

After a couple weeks of collecting stems, I'd add some dried boletes (slippery jacks from Chile) along with some spices, then cook, puree, strain and bottle. It was really, really good. The mushroom flavor, even made from cheap boletes and buttons, was deeply mushroomy and rich, and hit the menu soon after in the form of cream of mushroom soup, using mushroom ketchup to underline the earthy flavors.

The only problem was that I ran out too fast, so I started ordering product specifically to make the sauce, which is when I developed the version I'm sharing with you today: a version by the mushroom hunter, for the mushroom hunter.

Here's some takeaways I've learned over the years:

Tips

• Don't use the pores of mature boletes. Bolete pores have a tendency to produce a gelatinous, viscous ketchup. 
• Despite what other recipes will say online, don't puree the mushrooms. I like to pulse them in a food processor, or shred them through a food mill or food processor attachment. Pureeing will give you a cloudy finished sauce. That being said, it still tastes fine, and, you can always puree 4 cups with ½ teaspoon of xanthum gum to make a slightly thickened condiment--good in it's own right.
• Keep it in the fridge. Even though there's vinegar and salt, the salt is only a concentration of roughly 7-10% percent, where soy sauce is generally 16-20%. While it won't go rancid, I noticed some jars growing kahm yeast a few years ago, which while it won't hurt you, it can eventually create it's own flavors which isn't good. I've also had some jars feel pressurized and develop flavors of amonia, and although the flavor dissipated with cooking, it's still off-putting.
• Save the drained mushroom mash, dehydrate it, and use as a salt substitute. You can also dehydrate it, powder it, and add it back to the finished ketchup for a thicker, product, especially if you bind it with xanthum gum (see above).
• The best species is whatever large amount of fungus you have available. Common agarics, like the ones typically used in videos and online, can be difficult to source en-masse, but hens, chickens, and older boletes are great.

Use Ideas

I've done a lot of different things with the stuff over the years, but here's some favorites that won't fail you.

• Marinade. Season meat with a couple splashes a few hours or overnight before cooking. It will literally taste like mushroom flavored meat.
• Soy sauce substitute. Anywhere you would use soy sauce. See the image here with my shiitake egg rolls, or just use it as an excuse to eat a giant bowl of buttered rice.
• Fish sauce substitute. Use it in peanut sauce, kimchi, sweet and sour salad dressings, etc.
• Soups. Used in a soup, the ketchup will fade into the background (unless you use a ton of it) but it adds earthy undertones
• Sausages. There's still plenty of salt in this stuff, and salt (not seasonings) is what forms the myosin (the coagulative substance that gives sausage a good bite) Try using the ketchup in my puffball brat recipe.
• Pan sauce. This is one of the first things I read about using mushroom ketchup in, from the book A Taste of Scotland by Theodora Fitzgibbons. Cook some cutlets, deglaze the pan with a dash of wine, then add a splash of mushroom ketchup, and thicken the sauce lightly with roux, starch, or butter.

Variations 

• Double ketchup. Reduce the finished ketchup down by half (or even a little less, like ⅓) for a salt concentration similar to soy sauce, and a richer, darker, flavor.
• Different species. Every species will taste a little different. For mushrooms that give off a light colored juice, omit the Worcestershire to keep the color pure.
• Thickened. You can thicken this by pureeing 4 cups with ¼ teaspoon of xanthum gum, or by using rice flour, starch, then cooking and pureeing, etc. A thickened ketchup is a more powerful condiment, since it's not as watery and will cling to food.
• No waste ketchup. Use 2.5 lbs of mushrooms instead of 5, and puree everything until smooth after you're done for a thick paste/condiment--excellent with pureed soups and sauces.
• With dried mushrooms. I used to add dried slippery jacks, porcini, or whatever I had when I could.