Spicy Brown Mustard is a-mazing and works great for egg salad, tuna salad type stuff (tuna patty etc.) and soooo much more
You can also make homemade ketchup, or if you'er willing to splurge, heinz makes low sugar ketchup that's only 1g carb per serving (so you can make a burger!) land o lakes makes powdered butter flavor and cheese flavor, also 0/0/0 and allowed (in moderation). Life is full of season, use it!