A café menu offered:
garlic and herbed bread
I would unhesitatingly say and write herb bread, but herbed bread isn’t wrong. Google Ngrams shows that its used about a fifth to a quarter as much as herb bread. But a general Google search shows that some of those are in larger noun phrases like herbed bread twists and herbed bread pudding.
But herbed bread is awkward. Most adjectives ending in –ed are based on verbs. We can talk about buttered bread, which is bread which has been buttered. What are you doing? I’m buttering the bread. But herb is a noun. Herbed bread is not bread which has been herbed, but bread which has herbs. What are you doing? *I’m herbing the bread. (Butter was a noun first, but is now well and truly also a verb.)
There are three main groups of adjectives. The first are what for the want of a better term I will call ‘real adjectives’. An example is hot, which is related to the noun and verb heat but is not derived from them. Try our hot bread. It is bread which has been heated. The second are derived from nouns or verbs, for example lovely. It is not bread which has been loved, or which has love but bread which is like love (quite literally – the –ly ending is derived from the word like) (compare life-like and lively, for example). The third are derived from verbs, and end in –ing or –ed (or sometimes –t, –n or –en, in the case of irregular verbs). The first two groups readily take very, but not an –ly adverb like freshly, while the third group readily take freshly but not very: very hot bread v *freshly hot bread v freshly heated bread, very lovely bread v *freshly lovely bread v ?freshly loved bread, *very buttered bread v freshly buttered bread. (There’s more to it than that, but that’ll do as a general rule.)
The number of adjectives based on nouns is very small, and the ones I can immediately think of seem to want to be modified in some way: *a legged stool v a three-legged stool (all stools have legs) and ?heeled shoes v high-heeled shoes. (Some shoes do not have heels – I remember reading somewhere than lawn bowlers don’t wear heeled shoes. They certainly don’t wear high-heeled shoes. Note that it is also possible to say and write high-heel shoes.)
I don’t know if there’s a list of these noun+ed adjectives anywhere. Searching for ‘adjectives based on nouns’ found those in the love > lovely group, which is not what I wanted.
Meanwhile, if you’re writing a cafe menu, use herb bread, not herbed bread. Note that garlicked bread is almost plain wrong. It just exists, but only in combinations like oiled and garlicked bread, and I’m prepared to ignore the Twit who typed Pasta bollocknase, home garlicked bread plus warm choc and banana cake for afters.
PS Adding to the awkwardness are the clusters /bdbr/ in herbed bread and /kdbr/ in garlicked bread. I suspect that herb bread is often reduced to close to her bread.