Sugarless Condensed Milk
This is a good substitute for the canned variety. I have another condensed milk recipe (on this blog - only slightly lower in carbs at 2 grams), but it is for cold applications only. This recipe, although not terribly low-carb, is reduced carb and using, say 1/2 cup in a recipe spreads the roughly 22 grams of carbohydrates over the entire cake, cookie batch, cheesecake or whatever. I made this recipe last night when my pumpkin spice cheesecake came out a bit too savory tasting for my liking (I have a sweet tooth), so I poured a tablespoon over the top of each serving and that did the trick! This condensed milk is very much like the real thing. I could not tell the difference. This may or may not work in baking applications. Even although the taste is amazing, the composition is different to real condensed milk. Cold applications are probably still best here.

Note: There is now a product called coconut milk powder.  Perhaps it would work here or maybe half and half powdered milk and coconut milk powder.

1/2 cup boiling water
1 cup whole milk powder (apparently Nestle makes it, called NIDO and also KLIM - look at Publix or in a Super Walmart in the Hispanic section or in Costco and South America (PriceSmart))
Sweetener to equal 4 tbsp sugar
2 tbsp powdered erythritol
2 to 4 tbsp regular butter
1/4 tsp xanthan gum 

Place boiling water, whole milk powder, sweetener, erythritol, butter and xanthan gum in blender and blend until smooth. Allow to cool to room temperature before using in a recipe or store in refrigerator up to 1 week.

Yield: 1 1/4 cups, 1 tbsp per serving.
Nutritional Analysis:
42.1 calories, 1.7 g protein, 2.9 g fat, 2.5 g carbs