You're asking for two conflicting things.
Restaurant Char siu is made from mass manufactured sauces with a ton of red food coloring. And that too looks pretty darn dark as it goes on.
Authentic chinese char siu wil still be a dark sauce You adjust the redness with food coloring.
Here's a recent discussion with a recipe I've used that produces excellent char siu flavor. It's still a dark sauce, all the redness comes from food coloring, and as written, it's not red.
And as I say in that thread, the Lee Kum Kee jarred sauce is simpler with equal results.