Cinnamon Condensed Milk Butter Cake

Inspired by a cinnamon drink from Seoul Hotpot, I decided to add cinnamon to the condensed milk and swirl it. However, the batter for the cinnamon was too little to have a full taste. Glad that those who tried it said the cake is nice, and the cinnamon taste was good even though it was very little. 
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Recipe for Cinnamon Swirl Condensed Milk Butter Cake, adapted from A Family Feast.
(Makes a 7"cake)

Ingredients:
160g Plain flour
3/4tsp Baking powder
1/2tsp Sea salt
226g Unsalted butter, room temperature
40g Caster sugar
3 Large eggs
175g Sweetened condensed milk
2 tsp Vanilla extract

10g Cinnamon powder

Method:

1. Preheat oven to 180C. Line your 7" cake pan with baking paper.
2. In a bowl, sift together the flour, baking powder and salt and set aside.
3. In the bowl of a stand mixer fitted with a paddle attachment, cream the butter and sugar on high speed until light and fluffy – about 2 minutes. 
4. Add the eggs one at a time, mixing after each egg until well blended. 
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5. Add sweetened condensed milk and vanilla to the butter mixture and mix until combined.
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6. With the mixer on low, slowly add the dry mixture to the wet mixture (increasing the speed of the mixer as needed and scraping down the sides of the bowl as needed) until well combined.
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7. Take some batter out and mix in cinnamon powder until well incorporated.
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8. Pour the main batter into the prepared pan. Then randomly drop in the cinnamon batter. Swirl it with a skewer.
9. Bake for 50 minutes or until the top is golden brown and a toothpick inserted into the center of the cake comes out clean.
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10. Cool for 10 minutes, then turn the cake out onto a wire rack to cool completely.
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