A DIY Power supply system for a 150w high power led engine
The cheapo converter posted in the question will pop its output caps at 10A, they won't handle the converter's ripple current. No way. Be careful with these cheap chinese items, the specs are usually fantasy. Especially the "LM2596" ones, they're usually counterfeit chips.

Wiring a cheap converter at the output of a low quality switching power supply increases risk of trouble, and converting the voltage twice means more losses than using a simple offline constant current LED driver.

So, let's use an all-in-one constant current driver. These have an allowable output voltage range, and this must include the voltage range of your LED. Actual output voltage is determined by the LED, but it must be within the range allowed by the driver. 

Your LED has a Vf of 12-14V at its nominal current of 10A, so you can't use a driver than is limited to a max voltage of 12V in constant current mode.

Thus, a Meanwell HLG-150H-15 is a good fit. It delivers 10A constant current with an output voltage between 7.5V and 15V, which is what you need. Get the -B version if you want it dimmable. It is not expensive and it works.

You will also need a fan, and I'd definitely recommend a thermal shutdown sensor on the LED. Heatsinks and filters tend to clog up with dust over time.