Mayonnaise

Where I live, the big 3 are mustard, ketchup, and mayonnaise.

If I had to limit it to the "big 3" you listed, I would have to go for mustard. There are so many different types and of the options listed, mustard is easily the healthiest (or can be the healthiest) since a basic mustard is going to be low in sodium, sugar, and fat while also containing healthy phytonutrients.

Mustard is also much more versatile than folks in my part of the world give it credit for. It seems like a cultural thing / learned behavior rather than based on actual taste preferences. For instance, a fairly bland yellow mustard actually goes well with french fries. A spicy mustard (the types that are almost like horseradish) goes well with a variety of roasted veggies like broccoli, brussels sprouts, cauliflower. Honey mustard works well with chicken in various forms. Lots of cheeses pair well with different types of mustard. I could go on, but I'll stop here.

Since the majority of folks are discussing condiments that aren't in your "big 3", I would say that my actual favorite condiment is hot sauce. I'm not a connoisseur by any means and I don't have refined tastes. I don't even like super spicy hot sauces. But I do use hot sauce of some type with almost every meal and I go through a lot more of that than mustard or ketchup. Granted, hot sauces tend to be high in sodium, so I try not to go overboard.

Brown Sauce - HP, Daddies etc this sauce is pretty popular in the UK (Where I live) and goes great on chips/fries and prior dish mentioning.

I don't think Germany has this, usually.

For us the three big ones would be Mayo / Ketchup / Mustard I imagine. Of which personally, spiced Mayo always wins out (Miracle Whip). Just too used to it from my childhood. 😅

Hot sauce!

Spicy brown mustard, bonus if it's whole grain. Yellow mustard has its uses but is a sad excuse for mustard.

Ketchup is gross, it's so fucking sweet. If I wanted a sweet topping I'd use honey. It's like pouring corn syrup on your food.

Hot sauce is the real king seasoning

Brown sauce? Please, that's only a thing in Britain. The only sauce which defies national borders and cultures is mustard .

Ketchup is a western sauce. Mayo is an JP/K sauce. Hot sauce isn't even mentioned but is more widespread than brown sauce.

Spicy mustard. Yellow is acceptable for chili dogs (only).

As a general rule, I don't eat ketchup. My wife and kids love it, but I rarely have it. I normally eat my fries with nothing but some seasoning salt, but thick steak fries demand vinegar.

Actual barbecue sauce that isn’t a one-note, sweet sauce like I find in Asia but rather has tang, spiciness, & smokiness. I made some at home based on Gates sauce & gave some to locals who they were absolutely blown away that BBQ sauce can actually have a complex flavor flavor.

#2 would be sawmill gravy, #3 sweet chili, #4 jim jaew, #5 salsa verde, #6 tahini

Nowhere on my list & actually make me gag: ketchup, yellow mustard, brown sauce

Mayonnaise.

Mayo mixed with a spicy chili sauce.

I don't know what brown sauce is but of the other two definitely mustard. Can we add chilli sauce to the list though? That's what I put on everything.

Tartar sauce

Relish or mayo. Ketchup is too sweet and artificial-tasting, mustards are hit or miss for me.

Ketchup is pretty overpowered for anything but the blandest foods. I like mustard and/or mayo in most cases

"Brown sauce" isn't a thing in America - sauce that is brown and has no name is just gravy.

Anyway I'll stick with mustard mostly, paired with mayo on some subs.

A1 is my go to "cover up that awful shit so I can stomach eating it" sauce. Similarly good if somebody overcooks meat.

Marinara for dipping stuff into.

The only circumstances I'll accept for ketchup is when it comes by default on a burger, in which case I can't be bothered to care, paired with mayo at better burger joints.

Of those particular 3.....a good mustard I guess. I don't really use any of them.

Soy sauce

Chilli oil

Tomato sauce (fish and chips)

Where's Sriracha mayo at? Also normal mayo, garlic sauces like aioli, toum etc, here in Poland ground horseradish is the shit

if I have to stick with one, it's going to be ketchup, but ketchup slaps just right when it's got a dash of mustard in it. My favorite though is ketchup with Frank's Red Hot in it for fries

Brown sauce is not nearly as popular as hotsauce where I am. I always have a bottle of A1 and a bottle of catsup, but I typically have a half dozen each of mustards and hotsauces.

Editing to add I always have a jar of homemade chimichurri ready to go as well.

I hate ketchup as a sauce or spread, don't mind it as an ingredient but it's way too fucking sweet to put on anything.

Mayonnaise for sandwiches, with mustard or horseradish.

Hot sauce for eggs, beans or French fries (chips) . The salsa yucateca if I want hot without sour, Tabasco if I want sour; hot chili garlic paste if I want flavor bomb.

Also from the UK and I am, apparently, a normie, basic guy - ketchup all the way.

Out of the ones on your list, I'd probably go with Ketchup.

Outside of the list, BBQ sauce is my go to. I put that stuff on everything. Favorite is R&R's sauce and then Kinders after that.

Of those, ketchup for sure. It's simple, straightforward and combos well with most other things.

Just don't put it on pasta.

UK here, I love brown sauce on a fry up.

Sriracha mayo on chips.