To make the dressing: Combine the olive oil, vinegar, goat cheese, shallot, 1/4 teaspoon salt and some freshly ground black pepper in a jar. Tightly close the lid and shake until thoroughly combined. Set aside.
To make the salad: Combine the spring mix, romaine, tomatoes, radishes, pecans and goat cheese in a large bowl. Pour over the dressing and toss to combine. Adjust seasoning as needed. Serve immediately.