Add the peeled bananas into a large bowl. Using a potato masher, mash the bananas very well. If you do not have a potato masher, use a fork to mash the bananas.
Add the white sugar, brown sugar, vanilla and lemon juice.
Stir until blended.
Add this banana mixture to the slow cooker.
Cook on HIGH for 1.5 hours. You can cook this for 2 hours on high if you want a darker jam.
Stir and serve hot over ice cream or put into jars and refrigerate or freeze. The jam will thicken as it cools.
Video
Notes
Can I choose a different type of sweetener?I prefer white and brown sugar for it makes a wonderful flavored jam, though I understand some need to use a different sweetener. You can use any of these sweeteners below. You will need to add the sweetener slow cooker and taste before cooking.
Maple syrup will make the banana flavor a little stronger and give you an earthier tone to your jam while making it sweeter at the same time.
Honey is great if you're looking for something that tastes less sugary but still has that uniquely sweet quality of bananas while being lower in calories than other options with comparable sweetness levels.
Stevia works well too to lower the sugar content if you're looking for a keto-friendly or diabetic option.
How to store:
This small-batch banana jam makes 2-3 jars, depending on the size of your jars. It can be stored in a jar in the refrigerator once it's opened for about 2 weeks. The lemon juice does a nice job of keeping the bananas from oxidizing and turning brown.
You can also store the jam in an airtight container for up to six months in the freezer without any noticeable changes.
This is not a canning recipe for bananas have a low acidity level and canning can produce botulism.