This tip comes via Cadrys Kitchen.
She explains how it works:
I made some room in the freezer.
Then I lined a baking sheet with parchment paper.
With a measuring spoon, I doled out tomato paste in tablespoon-sized dollops like red tomato-y cookies.
I then popped the sheet into the freezer until the paste patties were solid.
Once they were completely frozen separately, I just moved the solid tomato paste patties into a glass container.
Check out the tip for yourself at the link below.
Quick Tip: Freeze Tomato Paste and Never Toss a Moldy Jar Again| Cadrys Kitchen
Photo byfishermansdaughter.