It's actually Matcha White Sesame ($10+), one of the recently introduced cakes at @stray.sg.

The exterior is what I'd assume to be a white chocolate matcha cream due to the distinguishable sweetness which resembles white chocolate, but for some reason a red bean-like taste lingers on after. Cutting into the cake would reveal a white sesame mousse with a rich matcha core that's rich enough to taste without being too bitter. The white sesame seems to be a little lost in translation with this one though.

On a separate note, lighting here is horrible here without sufficient natural light from the glass ceiling (it was raining and I used a torchlight and had to use a low f-stop 😢) so if photos are very important to you, do check the weather forecast. 🤷🏻‍♂️