Searing Smite

Level 1 Evocation (Paladin)
Casting Time: Bonus Action, which you take immediately after hitting a target with a Melee weapon or an Unarmed Strike Range: Self
Components: V
Duration: Template:Duration 1 minute

As you hit the target, it takes an extra 1d6 [[Fire damage] from the attack. At the start of each of its turns until the spell ends, the target takes 1d6 [[Fire damage] and then makes a Constitution saving throw. On a failed save, the spell continues. On a successful save, the spell ends.

Using a Higher-Level Spell Slot. All the damage increases by 1d6 for each spell slot level above 1.