The concept of money has continually evolved throughout history. Blockchain technology has emerged as a revolutionary platform for executing secure and transparent monetary transactions in the digital age. A stablecoin is a digital currency designed to maintain a stable value by being backed by some asset, such as a fiat currency like the US dollar. The advantages of stablecoins are mainly related to their stability, fast and low-cost transactions, transparency, and security. This work presents a comprehensive architecture for the back end of a stablecoin service, effectively enabling users to buy and sell this currency whenever they want to access the cryptocurrency market. One of the standout features of the proposed architecture is the bridge operation, which enables seamless cross-chain interoperability. It means that users can transition from one blockchain to another without reverting to a fiat currency, a critical step toward a more interconnected blockchain ecosystem. Aiming to demonstrate the feasibility of our proposal, we implemented a proof of concept using two EVM-compatible networks. The presented architecture serves as a secure and efficient reference for developing similar stablecoin systems already prepared to operate with cross-chain transactions.