Peel the kabocha squash and cut into about 5 mm thick pieces. Put the pieces in a microwave-safe container (a silicone steamer, etc.), add some water and cover with plastic wrap (or lid).
Heat the container from step 1 for about 2 minutes in a 600W microwave. Remove the wrap (or lid) and mash the kabocha using a masher or fork.
In a bowl, add the pancake mix, egg, sugar, milk and kabocha from step 2. Mix them well with a whisk.
Make the stewed apple: Cut the apple into quarters without peeling off its skin, and then remove its core. Cut into approx. 5 mm-thick wedges.
Put the apple slices in a frying pan with sugar, and butter. Mix well. Cook over medium heat with the lid on. (Stir occasionally.)
After about 2 minutes, take off the lid and cook for about 2 minutes over low to medium heat while stirring them. Turn off the heat once the liquid has reduced.
Add cinnamon powder and mix to coat the apple slices. Arrange the apple slices in a spiral pattern.
Gently pour the batter from Step 3 over the stewed apples from step 7. (Please be careful so the arranged apple wedges won't move.)
Cover the pan with a lid and cook for 10 to 12 minutes over low heat while keeping an eye on it. ( It is cooked once the middle of the batter starts to puff up.)
Turn off the heat and let it sit for 5 minutes with the lid still on. Place a plate faced upside down on the frying pan, flip the frying pan (with the plate) and remove the cake.
It'll look like this once it's cut.
Story Behind this Recipe
While I was making a lot of sweets using kabocha squash, I adapted this certain recipe I made before, "Cinnamon & Apple Pancake Mix Cake in a Frying Pan" (Recipe ID: 1385321), wondering what it'll taste like if I combine apple and kabocha.
During Step 1, please adjust the amount of water to be added and heating time according to the kind of kabocha squash you're using (i.e. the amount of water it contains). Please adjust the baking time while keeping an eye on the cake to make sure it doesn't burn, since there's going to be a difference in its browning depending on the size/material of the frying pan and how you control the heat.