Paper-pieced. Here are the sub-units, laid out in position. Keep track of what goes where!
And the final triangle, looking a little skewed because I always leave some extra fabric at the base, just in case the size is a wee small. Also, my latest applique attempt, four leaf clover. Trust me, readers, you need to use the reverse applique technique with this one. Oh yes, and don't use cheap black thread to baste your pieces in place. Traces of black may be transferred to your white fabric. Hopefully no one will get get close enough to see it.
viridian 118 blocks, 38 triangles!