In the bowl of a mixer, add the peanut butter and fresh milk. Beat with the whisk and add the condensed milk. Beat until you have a fluffy mixture. Using a spatula, transfer the mixture to a bowl and rinse the mixer bowl. Dry it well and add the cold whipped cream. Beat at medium speed for 4 minutes. Add the vanilla extract and increase the mixer speed slightly. Beat for another 2 minutes until you have a lightly whipped cream. It shouldn't be too thick. Remove the mixer bowl and pour in half of the peanut butter mixture. Gently stir with a spatula in circular motions to avoid deflating the whipped cream. Once the peanut butter is incorporated with the cream, add the remaining peanut butter mixture and one-third of the coarsely crushed pastelaki. Stir with the spatula again in circular motions until you have a fluffy mixture.
 
Take a rectangular cake mold with dimensions 13x31cm and lightly spray it with water (to make it easier for the plastic wrap to stick). Drain the excess water and line the mold with plastic wrap. Pour half of the cream mixture into the mold and sprinkle with half of the crushed pastelaki. Pour the remaining cream and cover it tightly with plastic wrap. Place it in the freezer for 6-8 hours until frozen. Invert the ice cream onto a serving plate and sprinkle with the remaining crushed pastelaki.