To peel whole fresh tomatoes, set the oven to broil/high and place the tomatoes in a line on the a baking sheet. Place the tomatoes in the oven directly under the flames, and broil just until the skins split, about 5 minutes. (Or use boiling water on the stovetop, see notes.) When cooled enough to handle, skin and chop the tomatoes.
Over medium heat, in a large saute pan, saute the shallot and garlic until just soft, about 2-3 minutes. Add the tomatoes, lemon juice and zest, balsamic vinegar and maple syrup, cook on medium heat about 10-15 minutes (or more if your tomatoes are very watery), until most of the liquid has cooked off. (Leave a little for the chia seeds to absorb.)
Stir in the chia seeds (and cayenne, if using) and remove from heat.
Allow to cool, them place in the refrigerator to chill and thicken for several hours overnight. (See notes for faster option.)
To remove the skins on the stovetop, place the tomatoes in a large pan of boiling water and heat just until the skins split, about 30 seconds or so. If doubling the recipe (or more), do the tomatoes in batches of about 4-5 each.I like the broiler method because I can peel my tomatoes before a pot of water will boil! But if you're going to double this recipe or more, the boiling water method would be faster.TipsTo make it faster:
You could substitute canned whole peeled tomatoes or skip peeling the tomatoes. But I like the fresh tomatoes without their skins best.
Rather than leave it in the fridge to set, you can add more chia seeds (a little at a time) and it will thicken soon after cooking. But be careful to make sure the chia seeds have fully swelled or they could present a choking hazard. I prefer the seeds-to-jam ratio achieved by following the recipe, so I like to use the several hours/overnight method.