Make Easy Caramel Sauce first OR make Caramel Sauce while the cake is cooking or cooling; it's flexible.
Choose pan size based on cooking method and preference: If you want to make the cake in a tall small pan like I did in the photos, the edges and top get pretty dark with oven-baking. So I lower the oven temp as I bake, to prevent burning, while still perfectly cooking the interior of the cake. This is one benefit of the IP cooking method, no outer darkened edges, so the whole cake stays super soft while the middle cooks perfectly. Both versions are great, but just know that. Of course, the other option is to bake Sticky Toffee Pudding in a 9" cake pan, so it won't be tall, but it also won't get too dark on the edges. I love my tall baked version and the IP small pan version, for the inner moist cake you get to really see. But the 9" cake pan is very alluring as well.
Oven version: Grease 7" Cheesecake Pan or 9" cake pan, and set aside.For Instant Pot: Grease 7-cup heatproof bowl or leak-proof cheesecake pan suitable for fitting inside your Instant Pot insert (like this). Set aside. Pour 2 cups water into Instant Pot insert. Place trivet into bottom of pot.
Recipe: In saucepan, bring water to a boil. Turn off heat, and add dates. Soak 1 hour.
While dates soften, combine dry ingredients in mixing bowl: cassava flour, coconut sugar, baking soda and sea salt.
In small bowl combine wet ingredients: melted butter, milk, egg and apple cider vinegar. Whisk briefly.
Preheat oven to 350° Fahrenheit.Place dates and water in blender. Purée 15 seconds.
Pour date purée into dry ingredients bowl. Add wet ingredients. Stir and fold together well without over-mixing.
Scrape contents into prepared pan, and briefly smooth the top surface.
Oven version: For 9" cake pan, bake until well puffed and golden brown, bounces back to the touch and a toothpick inserted in the center comes out mostly clean, about 25 minutes. For taller 7" cake pan, bake 20 minutes, then reduce oven temp to 325°F for 20 minutes, then reduce oven temp to 300°F for 10 minutes.Instant Pot version: Cover bowl or pan with tin foil over parchment paper and place pan in IP insert on top of trivet; or use parchment paper and place a small heatproof salad plate over the paper (to keep it down and somewhat dry during cooking).Seal Instant Pot lid. Make sure steam valve is shut. Press "Manual" button, and set the time to 30 minutes. When timer goes off, allow the pressure to release naturally for 25 minutes. Then press "Cancel" button, and open steam valve. Open lid and remove baking pan by using trivet handles and hot pads.Tilting the pan to one side slightly to allow any water to roll off, carefully remove tin foil (or plate and parchment). Allow cake to cool to room temperature. If using cheesecake pan, remove pan's sides. Remove cake from pan, and place on plate upside down. Using about half or more of the caramel, pour and spread warm caramel sauce all over cake's surface. Top with optional whipped cream (or coconut whipped cream). Or nest in a pool of Paleo Vanilla Custard.