The use of xanthan gum (XG) has been reported to soften the texture of gluten-free pasta (GFP), making it an ideal food for the elderly with swallowing difficulties. Designing pasta shapes can enhance the suitability of sauces, improving sensory properties. This study aimed to investigate the optimal amount of XG for softening the texture of GFP. Three-dimensional (3D) printing was used to create lattice design shapes of the soft GFP, and sauce adhesion capacity (SAC) was investigated. The viscoelastic properties and yield stress values of the GFP dough significantly increased with higher XG contents (0.25%–2%) (p < 0.05), improving ink printability. The X-1% sample showed a decrease in the storage modulus (G’) (representing solid-like behavior) curve when the temperature increased from 68 °C, correlating with its lower hardness (5.11 × 104 ± 480 N/m2), which almost matched level 2 as the soft solid food that can be mashed with gums. This also agreed with its reduction in water-holding capacity (WHC) and its larger microstructural porosities. The SAC test demonstrated a significant relationship between 3D lattice design shapes and sauce viscosity, concluding that high- or low-viscous sauces may be suitable for the larger or smaller size of interior hole designs, respectively. This study provides guidance for developing novel 3D-printed GFP with a soft texture specifically designed to improve the mealtime experience for the elderly.