Stamina templar build using crafted sets and a vanilla monster mask.

Best race: Dunmer. Orc, Khajiit (slightly less damage), and even Wood Elf will also work. 64 points into stamina.
Food - for parsing, Lava Foot Soup-And-Saltrice. In content, you can use  Braised Rabbit with Spring Vegetables for more HP and slightly higher damage.
Potions - Essence of Weapon Power or Alliance Battle Draught (stamina regen, weapon crit, weapon power).

Opening:
Cast Deadly Cloak and Solar Barrage, launch the Mages Guild ultimate Shooting Star, throw Barbed Trap, Power of the Light, Stampede, Vampire's Bane, Сarve.

Rotation:
Every sixth skill you should use Power of the Light (you can simply use it on cooldown). Next in priority are dots (damage over time skills).
Dot priority: Carve (don't let the stacks fall off), Solar Barrage, Stampede, Barbed Trap, Ritual of Retribution, Deadly Cloak, Vampire's Bane. For convenience, I place the dots in order of importance from left to right on the bar, making it easier to track which to activate. If all dots are active and there's nothing to activate, spam Biting Jabs.

Execute:

After the boss reaches 40% HP, the execute phase begins. Here we replace Biting Jabs with Radiant Glory (this morph is slightly weaker but provides mana sustain and excellent healing in content). Also, use Flawless Dawnbreaker ultimate instead of Shooting Star.
At around 25%, I cast Ritual of Retribution and Vampire's Bane one last time, as their uptime is no longer necessary.
After 10%, I keep only Stampede and Solar Barrage, and spam beam (Radiant Glory).

P.S. If it's not a problem for you to change potions during parsing, it's advisable to switch to Alliance Spell Draught or Essence of Spell Power for the execute phase. This will give you mana sustain and you can stop using Power of the Light after 20%, which will increase your damage slightly.