Heat the olive oil in a large, deep pan and cook the shallots for 2- 3 minutes over medium heat until slightly softened.
Add the garlic and continue to cook for 1 minute.
Stir in the orzo and toast it for 1-2 minutes, stirring often.
Add a third of the vegetable stock and bring to a simmer. Lower the heat and cook, stirring often, until most of the liquid is absorbed.
Repeat with another third of the stock, then add the remaining stock, frozen peas and baby spinach. Simmer, covered, for 2-3 minutes. The orzo should be al dente at this point.
Stir in the lemon juice, season to taste and serve immediately.
