Chard and charred are easily confused words.
The spell-check application of most word processing software programs would not catch a slip-up of these two words. Spell-check is looking for words that aren’t in its dictionary, and words that resemble words in its dictionary but are possibly spelled wrong. Spell-check isn’t perfect. It doesn’t know and can’t guess what word you wanted or what word you meant, it can only judge the words on the page. If you used words that are all spelled correctly, it gives you a pass anyway.
Autocorrect suggests words that start with the same letters. It’s suggesting what word you may want to save time, but quite often, its suggestions are pretty off base. They don’t help you out, but they do make you laugh.
Charred is the past tense of the verb char. If food is charred, it’s been grilled or roasted until it’s surface is blackened and blistered.
The following story uses both words correctly:
Charlotte was an adventurous vegetarian chef, offering innovative fusion cuisine. One of her most popular dishes combined charred squash and portobello mushrooms over a bed of swiss chard and garlic and herb with mashed turnip and cannellini beans.