The development of miniaturized embedded inductors holds crucial significance in advancing modern electronic devices, contributing to their size reduction, enhanced efficiency, and improved performance. This study introduces a groundbreaking, fully additive manufacturing process designed for fabricating miniaturized embedded double-stacked copper spiral inductors. The Sequential Build Up-Covalent Bonded Metallization (SBU-CBM) method serves as the foundation for this novel approach. The experimental process evolves in three stages. In Stage I, the first layer of polyurethane (PU1) is initially spin-coated onto the FR-4 base substrate. The lower embedded copper spiral inductor is then fabricated on top of PU1, employing the SBU-CBM method. Moving to Stage II, the second layer of polyurethane (PU2) is spin-coated onto the existing PU1 layer. Subsequently, a single microvia is created and copper-plated using the SBU-CBM method, establishing a crucial vertical connection between the upper and lower embedded copper spiral inductors. Finally, Stage III involves the fabrication of the upper embedded copper spiral inductor on PU2, utilizing the SBU-CBM method. Optical microscopy and X-ray Computed Tomography (XCT) images confirm the successful formation of embedded double-stacked copper spiral inductors, a configuration where two embedded copper spiral inductors are interconnected through a copper microvia. Notably, the copper strip lines within the spiral inductor configuration are miniaturized to a width of 10 μm, while the diameter of the microvias is reduced to 10 μm, indicating the miniaturization precision achieved through this novel additive manufacturing process.