In a large bowl, beat the softened salted butter and tub butter together until completely smooth and creamy.
Add the honey, Herbs de Provence, dried lavender, and flaky sea salt. Mix until everything is evenly incorporated throughout the butter.
Taste and adjust the honey, lavender, or salt to your preference.
Lay a large sheet of plastic wrap flat on the counter. Spoon the butter mixture into the center in a rough log shape.
Roll the plastic wrap tightly around the butter, twisting the ends to seal and compress it into a uniform log shape.
Refrigerate for at least 1 hour until firm, or freeze for 30 minutes for a faster set.
Slice into rounds and serve at room temperature.