In a small saucepan, heat the blackberries over medium heat. Bring to a gentle boil, then reduce heat and gently simmer until the berries soften and break apart, about 2-3 minutes. Stir frequently.
Using a fork or potato masher, mash the berries lightly, leaving some pieces. Stir in the maple syrup, lemon juice, vanilla, chia seeds and salt. Cook on low for another 1-2 minutes. The jam will thicken up more when cooled.
Remove from heat and let cool. Pour into an air-tight jar. This should last about a week in the fridge.
Notes
*If you'd like it a little sweeter, just add another ½ - 1 teaspoon of maple syrup.*If using frozen strawberries, let them thaw for 20-30 minutes.