Golden Hour is the main area in Penacony and there are 3 floors in this area, with a total of 37 treasure chests. While doing the guide, the official interactive map did not mark the 2 treasure maps (#27 and #31) so I edited it and added two circles.
First of all, if you have completed the Trailblaze Mission 'Long Day's Journey Into Night,' you should have 1 treasure chest counted because in the sub-mission 'Good Omen, My Friend,' you will be turned to Hanu (a small mafia guy) because of Sampo. In that state, you need to collect 1 treasure chest to progress in the mission. So I will start with #2 in the guide below.
2. Teleport to The Reverie Hotel Entrance and head east.
3. Behind a huge sign board.
4. At the far southeast area of the map, between the wall and the plants.
5. In front of the huge stairs.
6. At the far northeast area of the map, between a chair and two men.
7. At the outdoor dining area.
8. Solve the Dream Ticker puzzle to get the treasure chest.
9. Interact with the trash can and choose the correct option (Option 3 > Option 3). If you choose the wrong one, you will fight the trash can, but will still get the reward if you defeat it.
10. At the edge of the building.
11. Near the Clockie Food Truck.
12. Solve the Dream Ticker puzzle to get the treasure chest.
13. Beside the stairs.
14. At the outdoor dining area, near two small NPCs.
15. Solve the Dream Ticker puzzle to get the treasure chest.
16. In the small corner betwen the buildings.
17. Beside the Golden Capsule Machine
18. At the outdoor dining area.
19. Beside the stairs.
20. Behind the Popcorn Food Truck.
21. Between the plants and chairs.
22. Interact with the trash can and choose the correct option (Option 1 > Option 1). If you choose the wrong one, you will fight the trash can, but will still get the reward if you defeat it.
23. In front of the huge door with heart-clover-diamond-spade shapes on it.
24. Change into Hanu using the Hanu's Adventure and enter the vent beside it. There will be a Dream Jigsaw inside.
25. Inbetween the chairs near Clockie Statue.
26. Near Barrle and Barrle's Father.
27. Just beside the Bubble Pinball Machine.
28. Enter the Pinball Machine near the previous chest to reach F3. There, you will solve the Dream Ticker puzzle to get the treasure chest.
29. On the same floor, there is one treasure chest near the manhole.
30. Between the stairs and a chair.
31. Besides the stairs.
32. Behind the huge fountain.
33. In front of the huge billboard.
34. In front of another huge billboard.
35. Change into Hanu using the Hanu's Adventure and enter the vent beside it. There will be a chest hidden behind partitions.
36. Still inside the vent.
37. Change into a human and get the last treasure chest hanging on the air.