This isn’t really an answer to your question, but I have found that Amore brand tomato paste has better flavor than canned tomato pastes and it comes in a resealable metal tube, which you can store in the refrigerator and take out whenever you need a tablespoon or two of tomato paste.
It’s also more expensive than canned tomato pastes but you actually get the opportunity to use all of it rather than just a spoonful or two.
America’s Test Kitchen reviewed tomato pastes (subscription required link) and came to the same conclusion: Sold in a 4 1/2-ounce tube and priced at $2.49 (considerably higher than other tomato pastes), Amore Tomato Paste shined in our initial from-the-tube tasting—no cooking, no sauce.
Tasters described the product as “intense” and “fresh,” which may be because of the fat it contains.
It also scored points because of its tube packaging.
Just squeeze out what you need and store the rest in the fridge.
No fuss, no waste.
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I freeze it in ice cube trays or silicone muffin cups, then pop them out into a ziploc bag once they're frozen.
It's much cheaper to buy a big can and portion it up like this than to use the tiny cans or tubes.
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I always freeze it .
(zip-lock freezer bags, although at the price your quoting, wasting it might almost be cheaper :) )
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Personally I'd just eat it.
Toast some bread, stick some paste on top and then a little cheese, perhaps a bit of EVOO.
Perhaps a little basil if you have it.
Essentially a mini pizza - brilliant snack IMO.
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I buy tomato paste in a squeeze tube for that same reason.
I used to buy the can, and freeze leftovers in 1 tablespoon portions.
I'd toss one or two in soups or stews for a little bonus flavor.
I've been known to toss the remainder of the can into a bread recipe with a bit of dried basil and garlic.
For a simple side dish, I have sauteed some onions and garlic, added the remainder of the can of paste, then toss in an undrained can of french style green beans, and simmer for 15-20 minutes.
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I sometimes make sauces that use tomato paste. The problem is that usually I need only one or two tablespoons and I don't know what to do with the rest of the can. The smallest can I could find is 6 oz. and while it only costs 50 cents, I hate the thought of the rest going to waste. It's also not particularly flavorful.  Any ideas?
What do you do with left over tomato paste?
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<sauce><tomatoes><culinary-uses>
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You can buy tomato paste in resealable containers or squeeze tubes, which may also have more flavour. It can also be frozen in ice cube trays or silicone muffin cups. You can buy it in tubes that will keep for longer or freeze it.
Try using tomato paste in a tube. Freeze it into ice cube trays.