The Way of the Sun Soul monk (Xanathar's Guide to Everything, p. 35) gets the Radiant Sun Bolt feature at 3rd level:
You gain a new attack option that you can use with the Attack action. This special attack is a ranged spell attack with a range of 30 feet.
They also get the Searing Arc Strike feature at 6th level:
Immediately after you take the Attack action on your turn, you can spend 2 ki points to cast the burning hands spell as a bonus action.
The Spell Sniper feat (PHB, p. 170) has the following prerequisite:
Prerequisite: The ability to cast at least one spell
I was recently designing a Shadar-kai Monk who would take the Way of the Sun Soul archetype (ironic, I know). In the process, I began thinking about how he would benefit enormously from the Spell Sniper feat (increase his range from 30 to 60 ft). I then noticed the prerequisite on the feat and began thinking...
Does a ranged spell attack count as casting a spell (thus allowing the Sun Soul to pick up Spell Sniper at level 4)?
Or does the Sun Soul have to wait until he gains Searing Arc Strike at level 6 to qualify for Spell Sniper for his level 8 feat?