The phrase
"to increase the speed to high" means to make something go faster and reach its highest possible velocity.
Full definition
Once you have stiff peaks and the bowl is cool touch, start to add the butter on medium speed about 1 tablespoon at a time, when all the butter has been
added increase the speed to high and beat until the buttercream is smooth, creamy and shiny.
Increase the speed to high.
Increase speed to high and beat for one minute, until fluffy.
Add in the powdered sugar and stir slowly until incorporated;
increase speed to high and beat for another minute.
Increase speed to high and beat 2 minutes or until fluffy.
Once all butter has been added,
increase speed to high and beat 5 minutes.
Increase the speed to high and beat until light and fluffy, about 4 more minutes.
Increase speed to high and beat until firm peaks form.
Increase the speed to high and whisk until stiff peaks form, about 8 minutes.
Increase the speed to high and cream until light and fluffy.
Once you have added all of the syrup,
increase the speed to high.
Increase the speed to high and whisk until stiff, glossy peaks form, about 5 minutes more.
Increase the speed to high, and mix until light and fluffy, about 5 minutes.
Then add the powdered sugar,
increase the speed to high, and continue beating until it holds stiff peaks.
Then
increase the speed to high and mix until light and fluffy (approx. 2 minutes).
Increase speed to high; beat until light and fluffy (about 3 minutes).
Increase speed to high and whip until soft peaks form when whisk is lifted, about one minute.
Increase speed to high and beat to soft peaks (when whisk is lifted), about 1 minute, scraping down sides halfway through.
Increase speed to high and whip until soft peaks form when whisk is lifted, 15 to 60 seconds.
Increase speed to high and beat the frosting until smooth.
Increase speed to high, and gradually add granulated sugar and then cocoa mixture, 1 tablespoon at a time, beating until stiff peaks form.
With the mixer running on low, slowly add the confectioners» sugar to the butter and
increase speed to high.
Increase the speed to high and mix until light and fluffy.
Increase the speed to high and whip until stiff peaks are formed, about 5 - 7 minutes.
Whip on medium speed for 30 seconds, then
increase the speed to high and whip until the mixture holds stiff peaks and is double in volume.
Increase the speed to high and beat the meringue until cooled to room temperature, about 5 minutes.
Increase the speed to high and beat for an additional 2 minutes.
When all the sugar is added,
increase the speed to high and whip until firm, glossy peaks form.
Increase the speed to high, and beat until it is completely cool and a stiff peaked meringue forms (about 10 minutes).