In a large bowl, beat margarine and cream cheese by hand until fluffy.

Add sugar and milk slowly until mixture is completely smooth.

In a food processor, add half the can of macaroons and process until the macaroons become crumbs.

Repeat step three for second half of can.

Place a thick layer of red velvet crumbs inside a trifle bowl. Top with a layer of frosting. Repeat this process until number of desired layers is reached or bowl is full. End with frosting layer, and top with red velvet crumbs.