Use a mixer with a whisk attachment to whip one cup heavy whipping cream to firm peaks. That means the cream won't fall off when you flip over the whisk. Be careful! If you over whip cream, it will turn into butter.
Set aside the whipped cream (I slid it into another bowl) and put the paddle attachment on the mixer.
Cut the cream cheese into cubes.
Add the softened cream cheese and confectioner's sugar to the mixing bowl and blend until smooth. Make sure to scrape down the sides and paddle.
Add the Baileys and sour cream to the cream cheese. Mix well. Always scrape the sides and paddle.
Gently fold the whipped cream into the cream cheese mixture with a spatula.
Break up the graham cracker sheets and put them into a Ziploc bag.
Whack the graham crackers with something heavy (like a rolling pin) until they are crumbs.
Melt the butter.
Place the graham cracker crumbs into a bowl and add the melted butter.
Toss the crumbs and the butter thoroughly.
Begin assembling your parfait. Using an 8 ounce jar, begin with a layer of crumbs, add the cheesecake filling, more crumbs, and end with cheesecake.
Chill, covered (I used the lid), for at least three hours.
Top with chocolate curls, whipped cream, or salted caramel sauce, if desired.