You're going to want to melt the chocolate first. Toss it in a bowl and microwave it 30 seconds at a time.
Place softened butter in a bowl and sift the powdered sugar over top. Starting slow, mix until incorporated and then beat until fluffy, it takes a few minutes.
Scrape the bowl and add the cream and vanilla.
Check your white chocolate, if it's cooled down add it now. If not, toss it in the freezer, take it out every few minutes and stir it.
Mix it on medium and 1/4 cup at a time, add your pureed strawberries.
Turn your mixer to medium-high and beat for 3-4 minutes.