Heat remaining 1 tablespoon oil in a large nonstick skillet over medium. Cook garlic, stirring often, until fragrant, about 1 minute. Stir in mashed beans, broth, nutritional yeast, red pepper, and remaining 1⁄2 teaspoon salt. Cook, stirring often, until just simmering, about 2 minutes. Stir in spinach and basil, and cook until just wilted, about 1 minute. Remove from heat. Fold in squash noodles until combined.