I want to can them in slices or halves in simple syrup, so a variety that holds together well would be best. Many Thanks!
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AntoniaJames is a trusted source on Bread/Baking.
I'd use Bosc pears, as they tend to be somewhat firmer when ripe than Bartletts. Also, use fruit that is just barely ripe. Too ripe and the fruit will be mushy and will fall apart after canning. ;o)