Margarine (Best Option)
1:1 (1 cup margarine per 1 cup butter)Margarine is composed primarily of vegetable oils and water, formulated to emulate butter's fat content and melting characteristics. This similarity allows it to replicate butter's role in creating tender, flaky layers in cinnamon rolls by coating flour proteins and trapping steam during baking.
When substituting margarine, choose one with a high fat content (at least 80%) and avoid low-fat versions to ensure proper dough texture. Keep margarine chilled before use to mimic butter's plasticity and prevent greasy dough.
The final cinnamon rolls will have a slightly different flavor profile, often less rich and buttery, but the texture and rise remain very close to the original, making margarine the most reliable substitute.